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Screening of Chinese giant salamander meat hydrolysates with DPP-Ⅳinhibitory activity and systematic elucidation of their hypoglycemic functions in mouse model
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作者 Shucheng Li Changge Guan +5 位作者 Yi Wang Haihong Chen Wei Li Songjun Wang Chong Zhang Xinhui Xing 《Food Science and Human Wellness》 2025年第4期1305-1317,共13页
Type 2 diabetes(T2D)presents a significant health challenge,underscoring the need for functional foods and nutraceutical hypoglycemic bioactive peptides for its prevention.This study investigates the potential of prot... Type 2 diabetes(T2D)presents a significant health challenge,underscoring the need for functional foods and nutraceutical hypoglycemic bioactive peptides for its prevention.This study investigates the potential of proteolytic hydrolysate from artificially cultivated Chinese giant salamander(CGS)meat,a rich protein source,as a preventive strategy for T2D.We produced a CGS meat hydrolysate(CGSh)and demonstrated its ability to inhibit the T2D drug target dipeptidyl peptidaseⅣ(DPP-Ⅳ)through in vitro assays.We identified 5 peptides(WRPPDH,WAPPSKD,IPDSPF,IPEMIF,and VPIAVPT)with high DPP-Ⅳinhibitory activity in CGSh,suggesting its potential antidiabetic effects.In vivo experiments showed that CGSh effectively reduced insulin resistance in mice induced with a high-fat diet,as evidenced by a slower increase in blood glucose levels and a decreased HOMA-IR index.16S rRNA sequencing analysis revealed that CGSh improved gut microbial homeostasis,promoting beneficial microorganisms and reducing harmful bacteria.Metabolomic analyses identified an increase in valeric acid levels and highlighted nine potential biomarker metabolites.By inhibiting metabolic pathways such as AGE-RAGE,CGSh might also prevent diabetic complications and reduce inflammation.These findings suggest that CGSh has a promising hypoglycemic effect,making it a potential functional food ingredient for T2D prevention and treatment. 展开更多
关键词 chinese giant salamander Hypoglycemic effects Bioactive peptides Dipeptidyl dipeptidaseⅣ Multi-omics analysis
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移动微学习理论视角下的中文App教学设计分析——以HelloChinese为例
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作者 李姝姝 刘芳 曹洪豫 《国际中文教育(中英文)》 2025年第1期112-127,142,共17页
本研究在移动微学习理论指导下,以中文教学应用程序HelloChinese为研究对象,探究其在课程内容、教学理念和教学方法等方面的特点。课程内容等级方面,HelloChinese涵盖了相当于HSK1—4级和《国际中文教育中文水平等级标准》初等三级水平... 本研究在移动微学习理论指导下,以中文教学应用程序HelloChinese为研究对象,探究其在课程内容、教学理念和教学方法等方面的特点。课程内容等级方面,HelloChinese涵盖了相当于HSK1—4级和《国际中文教育中文水平等级标准》初等三级水平的内容;教学理念和方法上,该应用程序秉持游戏化、沉浸式、微型化和个性化的教学理念,采用了测试、播客和故事教学法。本研究建议开发者进一步深化应用程序的交互性和社交性学习功能,同时加强对测验练习质量的监控,并在游戏设计中融入更多竞争元素和层级挑战,以提升用户体验、增强学习成效。 展开更多
关键词 Hellochinese 教学应用程序 移动微学习理论 国际中文教育
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基于Chinese-CLIP模型和Prompt提示机制的图文检索方法
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作者 陈道彬 张子诺 +2 位作者 付裕彬 黎晋铭 林彬 《现代信息科技》 2025年第6期130-134,共5页
为提升图像文本匹配任务的准确率,提出了一种基于Chinese-CLIP模型和Prompt提示机制的图文检索方法。一方面,对文本数据进行预处理,去除停用词和标点符号后,利用BERT模型提取文本特征;另一方面,使用卷积神经网络提取图像特征,并将得到... 为提升图像文本匹配任务的准确率,提出了一种基于Chinese-CLIP模型和Prompt提示机制的图文检索方法。一方面,对文本数据进行预处理,去除停用词和标点符号后,利用BERT模型提取文本特征;另一方面,使用卷积神经网络提取图像特征,并将得到的文本与图像特征进行序列化,以实现多模态特征融合。模型训练时,先使用Chinese-CLIP大模型进行初步训练,再引入Prompt提示机制对模型进行微调。实验结果表明,所提方法在文搜图和图搜文两个任务上均有效地提升了准确率与召回率。 展开更多
关键词 图文检索 多模态特征融合 chinese-CLIP模型 Prompt提示机制
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The metabolic profiling of Chinese yam fermented by Saccharomyces boulardii and the biological activities of its ethanol extract in vitro
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作者 Xue Li Yiwen Shao +7 位作者 Limin Hao Qiaozhen Kang Xiaolong Wang Jiaqing Zhu Changcheng Zhao Yanling Shi Jike Lu Juanjuan Yi 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2718-2726,共9页
Chinese yam(Dioscorea opposita Thunb.),as one of the medicinal and edible homologous plants,is rich in various nutrients and functional factors.In this study,Chinese yam fermented by Saccharomyces boulardii was perfor... Chinese yam(Dioscorea opposita Thunb.),as one of the medicinal and edible homologous plants,is rich in various nutrients and functional factors.In this study,Chinese yam fermented by Saccharomyces boulardii was performed to investigate its bioactive components and metabolic profile.And then,the main bioactive components and biological activities of fermented Chinese yam ethanol extract(FCYE)were evaluated.Results showed that there were 49 up-regulated metabolites and 52 down-regulated metabolites in fermented Chinese yam compared to unfermented Chinese yam.Besides,corresponding metabolic pathways analysis initially revealed that the distribution of bioactive substances was concentrated on alcoholsoluble small molecular substances.Ulteriorly,the total polyphenol content and the total flavonoid content in FCYE were significantly increased,and the corresponding antioxidant and immunomodulatory activities in vitro were also significantly enhanced.Our study provided a new reference for the comprehensive utilization of Chinese yam and laid a theoretical foundation for the development and application of natural probiotic-fermented products. 展开更多
关键词 chinese yam Saccharomyces boulardii METABOLITES ANTIOXIDANT IMMUNOMODULATION
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Construction and Research Progress of the Chinese Meridian Project in 2022–2023
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作者 WANG Chi CHEN Zhiqing XU Jiyao 《空间科学学报》 CAS CSCD 北大核心 2024年第4期704-711,共8页
The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing... The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between layers.The construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second phase.The whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial space.The science community is looking forward to the great contribution of the CMP to space weather and space physics research. 展开更多
关键词 chinese Meridian Project(CMP) MAGNETOSPHERE IONOSPHERE Middle and upper atmosphere
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Research on the development methodology for clinical practice guidelines for organic integration of traditional Chinese medicine and Western medicine
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作者 Ying-Hui Jin Yan-Ping Wang +22 位作者 Ying-Lan Xie Gui-Hua Tian Xiao-Yu Zhang Nan-Nan Shi Ke-Hu Yang Xin Sun Yao-Long Chen Da-Rong Wu Xin-Feng Guo Long Ge Chen Zhao Cheng Lu Yin Jiang Jing Guo Si-Yu Yan Yong-Bo Wang Qiao Huang Xiang-Ying Ren Ying-Yue Rao Yun-Yun Wang Meng-Qian Yuan Xian-Tao Zeng Hong-Cai Shang 《Military Medical Research》 SCIE CAS CSCD 2024年第3期313-322,共10页
Integrated traditional Chinese medicine(TCM)and Western medicine(WM)is a new medical science grounded in the knowledge bases of both TCM and WM,which then forms a unique modern medical system in China.Integrated TCM a... Integrated traditional Chinese medicine(TCM)and Western medicine(WM)is a new medical science grounded in the knowledge bases of both TCM and WM,which then forms a unique modern medical system in China.Integrated TCM and WM has a long history in China,and has made important achievements in the process of clinical diagnosis and treatment.However,the methodological defects in currently published clinical practice guidelines(CPGs)limit its development.The organic integration of TCM and WM is a deeper integration of TCM and WM.To realize the progression of"integration"to"organic integration",a targeted and standardized guideline development methodology is needed.Therefore,the purpose of this study is to establish a standardized development procedure for clinical practice guidelines for the organic integration of TCM and WM to promote the systematic integration of TCM and WM research results into clinical practice guidelines in order to achieve optimal results as the whole is greater than the sum of the parts. 展开更多
关键词 METHODOLOGY Traditional chinese medicine Western medicine Organic integration Clinical practice guidelines(CPGs)
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Retention of harvest residues promotes the accumulation of topsoil organic carbon by increasing particulate organic carbon in a Chinese fir plantation
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作者 Jiamin Yang Ke Huang +5 位作者 Xin Guan Weidong Zhang Renshan Li Longchi Chen Silong Wang Qingpeng Yang 《Forest Ecosystems》 SCIE CSCD 2024年第5期720-727,共8页
Background As commonly used harvest residue management practices in subtropical plantations,stem only harvesting(SOH)and whole tree harvesting(WTH)are expected to affect soil organic carbon(SOC)content.However,knowled... Background As commonly used harvest residue management practices in subtropical plantations,stem only harvesting(SOH)and whole tree harvesting(WTH)are expected to affect soil organic carbon(SOC)content.However,knowledge on how SOC and its fractions(POC:particulate organic carbon;MAOC:mineral-associated organic carbon)respond to different harvest residue managements is limited.Methods In this study,a randomized block experiment containing SOH and WTH was conducted in a Chinese fir(Cunninghamia lanceolata)plantation.The effect of harvest residue management on SOC and its fractions in topsoil(0–10cm)and subsoil(20–40cm)was determined.Plant inputs(harvest residue retaining mass and fine root biomass)and microbial and mineral properties were also measured.Results The responses of SOC and its fractions to different harvest residue managements varied with soil depth.Specifically,SOH enhanced the content of SOC and POC in topsoil with increases of 15.9%and 29.8%,respectively,compared with WTH.However,SOH had no significant effects on MAOC in topsoil and SOC and its fractions in subsoil.These results indicated that the increase in POC induced by the retention of harvest residue was the primary contributor to SOC accumulation,especially in topsoil.The harvest residue managements affected SOC and its fractions through different pathways in topsoil and subsoil.The plant inputs(the increase in fine root biomass induced by SOH)exerted a principal role in the SOC accumulation in topsoil,whereas mineral and microbial properties played a more important role in regulating SOC dynamics than plants inputs in subsoil.Conclusion The retention of harvest residues can promote SOC accumulation by increasing POC,and is thus suggested as an effective technology to enhance the soil carbon sink for mitigating climate change in plantation management. 展开更多
关键词 chinese fir plantation Soil organic carbon Particulate organic carbon Mineral-associated organic carbon Harvest residue management
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“十七年”时期《中国文学》(Chinese Literature)“计划翻译模式”研究
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作者 钦佩 《中国当代文学研究》 CSSCI 北大核心 2024年第3期25-38,共14页
“十七年”时期以《中国文学》(Chinese Literature)和外文出版社为代表的国家翻译机构翻译实践形成了一种特殊的翻译模式,即“计划翻译模式”。首先,作为中国文学对外翻译的组织者与业务负责人,叶君健经过“下乡”完成知识分子身份认... “十七年”时期以《中国文学》(Chinese Literature)和外文出版社为代表的国家翻译机构翻译实践形成了一种特殊的翻译模式,即“计划翻译模式”。首先,作为中国文学对外翻译的组织者与业务负责人,叶君健经过“下乡”完成知识分子身份认同和思想认识的改造。其次,作为冷战时期中国国家对外文化交流的窗口,《中国文学》精心设计翻译策略,开展国家文学翻译实践。再次,作为国家翻译机构和国家文化单位,外文出版社服务于国家对外宣传的翻译目的。最后,翻译界经过组织化、计划化的整合,成为社会主义文化建设的工具,中国文学对外翻译是冷战时期重要的国家文化工程。 展开更多
关键词 “计划翻译模式” 《中国文学》(chinese Literature) 叶君健 对外翻译
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A Study on the Cross-Cultural Adaptation of International Chinese Teachers at Confucius Institutes in South Korea
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作者 Fu Qiong 《国际中文教育(中英文)》 2024年第4期51-70,共20页
International Chinese teachers are one of the determinants of the quality development of Confucius Institutes,and their cross-cultural sociocultural adaption,psychological adaption,and job adaption are in need of in-d... International Chinese teachers are one of the determinants of the quality development of Confucius Institutes,and their cross-cultural sociocultural adaption,psychological adaption,and job adaption are in need of in-depth investigation and research.Based on previous research,this paper analyzed the cross-cultural adaptation of international Chinese teachers at Confucius Institutes in South Korea during 2022-2023 through surveys and personal interviews.The study found that the teachers’adaptation was best in terms of work,followed by sociocultural adaptation,and weakest in terms of psychological adaptation.In terms of work adaptation,attention should be focused on adapting to teaching language and teaching methods.In terms of sociocultural adaptation,the focus should be on adapting to personal communication.In terms of psychological adaptation,attention should be paid to feelings of loneliness and anxiety.The study also focused on the internal and external factors influencing their cross-cultural adaptation,as well as the true inner feelings of international Chinese teachers.The study found that factors such as English proficiency,gender,education,professional background,and overseas experience had little impact on teachers’cross-cultural adaptation,while factors such as Korean proficiency,participation in cross-cultural training before going to South Korea,understanding of Korean culture before going to South Korea,and length of time spent in working in South Korea had a greater impact on the cross-cultural adaptation of the research subjects.This study provides reliable reference materials for international Chinese teachers going to South Korea to improve their cross-cultural adaptation abilities and promote the reform and innovation of international Chinese education. 展开更多
关键词 international chinese teachers cross-cultural adaptation South Korea Confucius Institutes
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Recent Progress in Space Science and Applications on Chinese Space Station in 2022–2024
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作者 GU Yidong GAO Ming +4 位作者 ZHAO Guangheng WANG Qiang LYU Congmin ZHONG Hongen LIU Guoning 《空间科学学报》 CAS CSCD 北大核心 2024年第4期607-621,共15页
Chinese Space Station(CSS)has been fully deployed by the end of 2022,and the facility has entered into the application and development phase.It has conducted scientific research projects in various fields,such as spac... Chinese Space Station(CSS)has been fully deployed by the end of 2022,and the facility has entered into the application and development phase.It has conducted scientific research projects in various fields,such as space life science and biotechnology,space materials science,microgravity fundamental physics,fluid physics,combustion science,space new technologies,and applications.In this review,we introduce the progress of CSS development and provide an overview of the research conducted in Chinese Space Station and the recent scientific findings in several typical research fields.Such compelling findings mainly concern the rapid solidification of ultra-high temperature alloy melts,dynamics of fluid transport in space,gravity scaling law of boiling heat transfer,vibration fluidization phenomenon of particulate matter,cold atom interferometer technology under high microgravity and related equivalence principle testing,the full life cycle of rice under microgravity and so forth.Furthermore,the planned scientific research and corresponding prospects of Chinese space station in the next few years are presented. 展开更多
关键词 chinese Space Station(CSS) Space material science Micro-gravity fluid physics Fundamental physics Space life sciences and biotechnology
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Networking Observation and Applications of Chinese Ocean Satellites
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作者 ZOU Bin LIU Yuxin 《空间科学学报》 CAS CSCD 北大核心 2024年第4期722-730,共9页
This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural la... This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural launch in 2002,China has achieved substantial advancements in ocean satellite technology,forming an observation system composed of the HY-1,HY-2,and HY-3 series satellites.These satellites are integral to global ocean environmental monitoring due to their high resolution,extensive coverage,and frequent observations.Looking forward,China aims to further enhance and expand its ocean satellite capabilities through ongoing projects to support global environmental protection and sustainable development. 展开更多
关键词 chinese ocean satellites Networking observation Ocean forecasting Ocean disaster prevention and mitigation Ocean ecological monitoring Ocean resource development Polar monitoring Terrestrial applications
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Chinese named entity recognition with multi-network fusion of multi-scale lexical information
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作者 Yan Guo Hong-Chen Liu +3 位作者 Fu-Jiang Liu Wei-Hua Lin Quan-Sen Shao Jun-Shun Su 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第4期53-80,共28页
Named entity recognition(NER)is an important part in knowledge extraction and one of the main tasks in constructing knowledge graphs.In today’s Chinese named entity recognition(CNER)task,the BERT-BiLSTM-CRF model is ... Named entity recognition(NER)is an important part in knowledge extraction and one of the main tasks in constructing knowledge graphs.In today’s Chinese named entity recognition(CNER)task,the BERT-BiLSTM-CRF model is widely used and often yields notable results.However,recognizing each entity with high accuracy remains challenging.Many entities do not appear as single words but as part of complex phrases,making it difficult to achieve accurate recognition using word embedding information alone because the intricate lexical structure often impacts the performance.To address this issue,we propose an improved Bidirectional Encoder Representations from Transformers(BERT)character word conditional random field(CRF)(BCWC)model.It incorporates a pre-trained word embedding model using the skip-gram with negative sampling(SGNS)method,alongside traditional BERT embeddings.By comparing datasets with different word segmentation tools,we obtain enhanced word embedding features for segmented data.These features are then processed using the multi-scale convolution and iterated dilated convolutional neural networks(IDCNNs)with varying expansion rates to capture features at multiple scales and extract diverse contextual information.Additionally,a multi-attention mechanism is employed to fuse word and character embeddings.Finally,CRFs are applied to learn sequence constraints and optimize entity label annotations.A series of experiments are conducted on three public datasets,demonstrating that the proposed method outperforms the recent advanced baselines.BCWC is capable to address the challenge of recognizing complex entities by combining character-level and word-level embedding information,thereby improving the accuracy of CNER.Such a model is potential to the applications of more precise knowledge extraction such as knowledge graph construction and information retrieval,particularly in domain-specific natural language processing tasks that require high entity recognition precision. 展开更多
关键词 Bi-directional long short-term memory(BiLSTM) chinese named entity recognition(CNER) Iterated dilated convolutional neural network(IDCNN) Multi-network integration Multi-scale lexical features
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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO_2 extraction on Chinese fir 被引量:9
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,共5页
Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of se... Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of seed germination. The results showed thatas to the available rate of allelochemicals, the pressure and temperature of extraction were themost important factors. The allelochemicals of Chinese-fir root extracted by pure CO_2 and ethanolmixed with CO_2 have different allelopathic activities to seed germination, and the allelochemicalsextracted by ethanol mixed with CO_2 had stronger inhibitory effects on seed germination than thatextracted by pure CO_2. 展开更多
关键词 chinese fir autointoxication supercritical CO_2 extraction BIOASSAY SEEDGERMINATION
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Humanistic Spirit Contained in Traditional Chinese Medicine should Be Valued 被引量:3
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作者 吴群励 梁晓春 《Chinese Medical Sciences Journal》 CAS CSCD 2019年第1期51-54,共4页
Medicine is a science studying human's health and diseases as well as the regularity between them. Its research subject is human, who possess natural attribute, psychological attribute and social attribute. Theref... Medicine is a science studying human's health and diseases as well as the regularity between them. Its research subject is human, who possess natural attribute, psychological attribute and social attribute. Therefore, medicine is bound to possess humanistic attribute. Rooted in Chinese traditional culture, Traditional Chinese Medicine contains abundant humanistic thoughts, for instance, pursuing the unity of human and nature, advocating the vital importance of life, sticking to the virtue of "medicine being humane art", abiding by the principle of "Benevolence prior to interest", complying with the medical rule of "Respecting peers". These are the very concrete reflections of medical humanistic spirit. In this article we aim to explore the humanistic thoughts contained in Traditional Chinese Medicine, and try to inherit and carry forward the spirit to better relieve the tensions between doctors and patients and improve the quality of medical services. 展开更多
关键词 Traditional chinese Medicine HUMANISTIC SPIRIT DOCTOR-PATIENT relationship medical ETHICS
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Biomass, litterfall and the nutrient fluxes in Chinese fir stands of different age in subtropical China 被引量:18
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作者 马祥庆 刘春江 +2 位作者 Ilvesniemi Hannu Carl J.Westman 刘爱琴 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期165-170,250,共6页
Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), a fast-growing, ever-green conifer tree with high yield and excellent quality, is the most important tree species of timber plantations in subtropical China. We inv... Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), a fast-growing, ever-green conifer tree with high yield and excellent quality, is the most important tree species of timber plantations in subtropical China. We investigated the characteristics of biomass, litterfall and nutrient fluxes in the 8, 14 and 24 year-old stands, representing the young, middle-aged and mature stands. The results showed that Chinese fir plantations in central Fujian province had high productivity, and the proportion of stem mass in total biomass was between 50%-70%. Chinese fir was low nutrient-return tree species with litterfall. Nutrient withdrawal from senescing needles was a strong age-dependence for nitrogen, phosphorous and potassium in Chinese fir. With a management system of such short-rotation and continuously pure-crop planting, harvesting timber can lead to great nutrient loss, which may be one of the causes for site degradation. 展开更多
关键词 chinese fir BIOMASS PRODUCTIVITY Litter fall Nutrient flux
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Soil microbial properties and nutrients in pure and mixed Chinese fir plantations 被引量:16
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作者 王清奎 汪思龙 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第2期131-135,共5页
An investigation on soil organic carbon, total N and P, NO3-N, available P, microbial biomass C, N and P, basal respiration and metabolic quotients (qCO2) was conducted to compare differences in soil microbial prope... An investigation on soil organic carbon, total N and P, NO3-N, available P, microbial biomass C, N and P, basal respiration and metabolic quotients (qCO2) was conducted to compare differences in soil microbial properties and nutrients between 15-year-old pure Chinese fir (Cunninghamia lanceolata) and two mixed Chinese fir plantations (mixed plantations with Alnus crernastogyne, mixed plantations with Kalopanax septemlobus) at Huitong Experimental Station of Forest Ecology (26°45′N latitude and 109°30′E longitude), Chinese Academy of Sciences in May, 2005. Results showed that the concentrations of soil organic carbon, total N, NO3^--N, total P and available P in mixed plantations were higher than that in pure plantation. Soil microbial biomass N in two mixed plantations was averagely higher 69% and 61% than that in pure plantation at the 0-10 cm and 10-20 cm soil depth, respectively. Soil microbial biomass C, P and basal respiration in mixed plantations were higher 11%, 14% and 4% at the 0-10 cm soil depth and 6%, 3% and 3% at the 10-20 cm soil depth compared with pure plantation. However, soil microbial C: N ratio and qCO2 were averagely lower 34% and 4% in mixed plantations than pure plantation. Additionally, there was a closer relation between soil microbial biomass and soil nutrients than between basal respiration, microbial C: N ratio and qCO2 and soil nutrients. In conclusion, introduction of broad-leaved tree species into pure coniferous plantation improved soil microbial properties and soil fertility, and can be helpful to restore degraded forest soil. 展开更多
关键词 chinese fir mixed plantation soil microbial biomass soil nutrient
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Studies on preparations and analysis of essential oil from Chinese fir 被引量:11
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作者 黄洛华 秦特夫 大平辰郎 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期80-82,J004,共4页
Three steam distillation devices (D-1, D-2 and D-4) or one simultaneous distillation (D-3, water-diethyl ether) as well as the process of CO2-SFE (Supercritical fluid extraction) were adopted in extraction of essentia... Three steam distillation devices (D-1, D-2 and D-4) or one simultaneous distillation (D-3, water-diethyl ether) as well as the process of CO2-SFE (Supercritical fluid extraction) were adopted in extraction of essential oils from Chinese-fir (Cunninghamia lancedata (Lamb) Hook.) and the chemical components of the extracted essential oil were analyzed by Gas chromatograph-MS analyses. The results showed that the essential oil could be almost extracted out within 2 hours and the device-3 had the highest extraction efficiency. The major chemical component of the oil was cedrol. The yield of the extracted essential oils from Chinese fir decreased gradually with the increase of the distillation time. The best condition for extraction by means of CO2-SFE is 100 kg·cm?2 in pressure and 40°C in temperature for. Keywords Chinese fir - Essential oil - Cedrol - Supercritical fluid extraction CLC number S781.4 Document code A Foundation item: This paper was support by the Key Foundation Research Project (G1999016001) of China and the Japan International Cooperation AgencyBiography: HUANG Luo-hua (1957-), male, Research associate, Research Institute of Wood Industry, Chinese Academy of forestry, Beijing 100091, P. R. ChinaResponsible editor: Song Funan 展开更多
关键词 chinese fir Essential oil CEDROL Supercritical fluid extraction
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Seasonal Dynamics of Energy Return Through Litterfall of A Mixed Forest of Chinese Fir and T. odorum 被引量:1
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作者 杨玉盛 陈光水 +2 位作者 何宗明 李秀芳 陈银秀 《Forestry Studies in China》 CAS 2001年第1期26-31,共6页
Based on the measurement of monthly litterfall and their gross calor ic values, the seasonal dynamics of energy return through litterfall were determ ined in a pure and a mixed T. odorum (Tsoongiodendron odorum Chun) ... Based on the measurement of monthly litterfall and their gross calor ic values, the seasonal dynamics of energy return through litterfall were determ ined in a pure and a mixed T. odorum (Tsoongiodendron odorum Chun) forests with Ch inese fir (Cunninghamia lanceolata (Lamb.) Hook.) in Sanming, Fujian Provinc e. Annual ene rgy return through litterfall was estimated as 12.648×10 6J·m -2 for the mixed fo rest, being 4 2% higher than that of the pure forest, and a large proportion of the energy return comprised leaf litter. The conversion efficiency of solar rad i ation energy into litterfall was 0 56% for mixed forest and 0 54% for pure for es t, respectively. The monthly energy flux in litterfall of Chinese fir showed a t hree-apex curve, peaked in March, August and December, respectively, which was s imilar to that in various fractions of leaf, twig, flower and fruit litter. The consistency in monthly patterns among different litter fractions of Chinese fir was attributed to their solid connections all the while. The monthly energy flux in litterfall of T. odorum culminated in January, May and August, the same was true for its leaf and twig litter. However, energy flux in flower litter only oc curred during March to May and that in fruit litter appeared in January and Marc h. The monthly dynamics of energy flux through litterfall of the two forests wer e both determined by their respective litterfall pattern of Chinese fir. Seasona l energy flux in litterfall for both mixed and pure forests followed the sequenc e of spring>winter>summer>autumn, but fluctuations in the former were less disti nct than those in the latter. 展开更多
关键词 chinese fir mixed forest LITTERFALL energy flux s easonal dynamics
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Population genetic diversity and regional differentiation of Chinese forest frog s (Rana chensinensis) in Heilongjiang Province 被引量:6
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作者 肖向红 郑冬 +1 位作者 李枫 刘学东 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期40-42,共4页
The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields o... The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on. 展开更多
关键词 chinese forest frogs (Rana chensinensis) Population genetics Regiona l differentiation
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Fixation and Creep of Compressed Wood of Chinese Fir Irradiated with Gamma Rays 被引量:1
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作者 王洁瑛 赵广杰 《Forestry Studies in China》 CAS 2001年第1期58-65,共8页
In order to discuss the mechanisms of permanent fixation of wood compression set , compressed wood of Chinese fir (Cunninghamia lanceolata) was irradiated by gamma rays from 60 Co. The irradiation doses wer... In order to discuss the mechanisms of permanent fixation of wood compression set , compressed wood of Chinese fir (Cunninghamia lanceolata) was irradiated by gamma rays from 60 Co. The irradiation doses were 0 (for match specim ens), 10 3, 5×10 3, 10 4, 5×10 4, 10 5, 5×10 5, 10 6, 5×10 6 Gy, res pectively. Then the weight loss, the equilibrium moisture content (EMC), the rec overy of wood compression set after adsorption (RSA) and the recovery after imme rsion in water (RSW), as well as the creep behaviour under a dry specimen condit ion and under an adsorption and subsequent desorption condition were measured an d discussed. This research proves that the doses of gamma irradiation have great effect on weight loss, EMC, RSA, RSW of irradiated compressed wood of Chinese f ir. The weight loss and the EMC increase, the RSA and the RSW fall drastically w hen the irradiation doses exceed 10 6 Gy. Both the instantaneous compliance and the creep compliance of the irradiated specimens under the two measurement cond itions show the general trend of increase with the increase of gamma irradiation doses. It can be deduced that decomposition or decrystallization reactions happ en in the wood cell wall at high gamma irradiation doses, especially at doses of around 5×10 6 Gy. In addition, this research proves that decomposition of mai n components of cell wall of compressed wood will lead to fixation of compressio n set of wood to a certain degree. 展开更多
关键词 gamma irradiation compressed wood chinese fir fixa tion CREEP
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