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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage 被引量:1
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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The first discovery of Holocene Ailuropoda melanoleuca subfossils from Xiangxi,Hunan,China
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作者 TONG Guang-Hui LIU Li +2 位作者 LI Yong-Xiang WANG Wen-Zhe CAI Xing-Lin 《古脊椎动物学报(中英文)》 北大核心 2025年第3期242-247,共6页
A new cranium and two mandibles of Ailuropoda melanoleuca from Xiangxi,Hunan Province are described here.The materials were discovered in a karst cave on the Bamian Mountain at an altitude of 1200 m,with AMC carbon-fo... A new cranium and two mandibles of Ailuropoda melanoleuca from Xiangxi,Hunan Province are described here.The materials were discovered in a karst cave on the Bamian Mountain at an altitude of 1200 m,with AMC carbon-fourteen isotope dating indicating an age of 2800±30 BP.Historically,the giant panda was widely distributed in southern China and parts of Southeast Asia during the Pleistocene epoch,but it is now confined and isolated to six mountain ranges in southwest China’s Sichuan,Shaanxi,and Gansu provinces.The subfossil materials reported here represent the first discovery of the living species of giant panda in Xiangxi,Hunan.This extends their geographical distribution in southern China during the Holocene epoch eastward to the eastern edge of the Yunnan-Guizhou Plateau and their recent altitude range down to 1200 m. 展开更多
关键词 Xiangxi hunan Bamian Mountain HOLOCENE Ailuropoda melanoleuca
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Effect of Coix Seed on the Rheological and Structural Properties of Wheat Dough and Noodle Quality
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作者 WU Yingmei XU Longquan +4 位作者 YU Yunliu LUO Guangjie WANG Chengli PU Dingfang HUANG Qun 《食品科学》 北大核心 2025年第11期64-75,共12页
The effect of coix seed flour(0%–25%)on the rheological and structural properties of wheat dough and noodle quality was investigated.The addition of coix seed flour was found to enhance the elasticity of dough,which ... The effect of coix seed flour(0%–25%)on the rheological and structural properties of wheat dough and noodle quality was investigated.The addition of coix seed flour was found to enhance the elasticity of dough,which may be attributed to the fact that small starch particles increase the filling capacity within the dough matrix.This increase subsequently resulted in more complete and uniform structure of dough.Moreover,setback viscosity rose to 1095 cP.The rapid water absorption of coix seed starch led to changes in the secondary structure of proteins in dough.The proportion ofβ-sheet markedly increased,whereas the proportion ofα-helix decreased with increasing level of coix seed flour substitution.Meanwhile,coix seed flour substitution significantly reduced the estimated glycemic index of noodles.Correlation analysis revealed that pasting parameters had significant effects on the evaluation of noodle quality.This study provides a foundation for researchers to substitute wheat flour with coix seed flour. 展开更多
关键词 coix seed DOUGH PROPERTIES noodle quality
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Assessing fiber quality variability among modern upland cotton cultivars and incorporating it into the GOSSYM-based fiber quality simulation model
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作者 BEEGUM Sahila HASSAN Muhammad Adeel +2 位作者 REDDY Krishna N. REDDY Vangimalla REDDY Kambham Raja 《Journal of Cotton Research》 2025年第2期213-227,共15页
Background GOSSYM is a mechanistic,process-based cotton model that can simulate cotton crop growth and development,yield,and fiber quality.Its fiber quality module was developed based on controlled experiments explici... Background GOSSYM is a mechanistic,process-based cotton model that can simulate cotton crop growth and development,yield,and fiber quality.Its fiber quality module was developed based on controlled experiments explicitly conducted on the Texas Marker^(-1)(TM1)variety,potentially making its functional equations more aligned with this cultivar.To assess the model’s broader applicability,this study analyzed fiber quality data from 40 upland cotton cultivars,including TM1.The measured fiber quality from all cultivars was then compared with the modelsimulated fiber quality.Results Among the 40 upland cultivars,fiber strength varied from 28.4 cN·tex^(-1) to 34.6 cN·tex^(-1),fiber length ranged from 27.1 mm to 33.3 mm,micronaire value ranged from 2.7 to 4.6,and length uniformity index varied from 82.3%to 85.5%.The model simulated fiber quality closely matched the measured values for TM1,with the absolute percentage error(APE)being less than 0.92%for fiber strength,fiber length,and length uniformity index and 4.7%for micronaire.However,significant differences were observed for the other cultivars.The Pearson correlation coefficient(r)between the measured and simulated values was negative for all fiber quality traits,and Wilmotts’s index of agreement(WIA)was below 0.45,indicating a strong model bias toward TM1 without incorporating cultivar-specific parameters.After incorporating cultivar-specific parameters,the model’s performance improved significantly,with an average r-value of 0.84 and WIA of 0.88.Conclusions The adopted methodology and estimated cultivar-specific parameters improved the model’s simulation accuracy.This approach can be applied to newer cotton cultivars,enhancing the GOSSYM model’s utility and its applicability for agricultural management and policy decisions. 展开更多
关键词 COTTON GOSSYM Crop modeling Fiber quality Cultivar-specific parameter
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Critical quality indicators of high-performance polyetherimide(ULTEM)over the MEX 3D printing key generic control parameters:Prospects for personalized equipment in the defense industry
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作者 Nectarios Vidakis Markos Petousis +6 位作者 Constantine David Nektarios K.Nasikas Dimitrios Sagris Nikolaos Mountakis Mariza Spiridaki Amalia Moutsopoulou Emmanuel Stratakis 《Defence Technology(防务技术)》 2025年第1期150-167,共18页
Additive Manufacturing(AM)can provide customized parts that conventional techniques fail to deliver.One important parameter in AM is the quality of the parts,as a result of the material extrusion 3D printing(3D-P)proc... Additive Manufacturing(AM)can provide customized parts that conventional techniques fail to deliver.One important parameter in AM is the quality of the parts,as a result of the material extrusion 3D printing(3D-P)procedure.This can be very important in defense-related applications,where optimum performance needs to be guaranteed.The quality of the Polyetherimide 3D-P specimens was examined by considering six control parameters,namely,infill percentage,layer height,deposition angle,travel speed,nozzle,and bed temperature.The quality indicators were the root mean square(Rq)and average(Ra)roughness,porosity,and the actual to nominal dimensional deviation.The examination was performed with optical profilometry,optical microscopy,and micro-computed tomography scanning.The Taguchi design of experiments was applied,with twenty-five runs,five levels for each control parameter,on five replicas.Two additional confirmation runs were conducted,to ensure reliability.Prediction equations were constructed to express the quality indicators in terms of the control parameters.Three modeling approaches were applied to the experimental data,to compare their efficiency,i.e.,Linear Regression Model(LRM),Reduced Quadratic Regression Model,and Quadratic Regression Model(QRM).QRM was the most accurate one,still the differences were not high even considering the simpler LRM model. 展开更多
关键词 Polyetherimide(PEI) Material extrusion(MEX) Three-dimensional printing(3D-P) Critical quality indicators(CQIs) Quadratic regression model(QRM) Taguchi
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我国开放大学在线课程质量评价研究——来自美国Quality Matters的启示 被引量:23
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作者 陈然 张晓 唐荣 《成人教育》 北大核心 2020年第2期27-32,共6页
在线课程是开放大学远程教学的特色,其质量优劣直接影响到开放大学的办学质量和办学声誉。提高课程质量,离不开科学有效的质量评价体系,然而,目前,我国开放大学课程质量评价发展相对滞后,难以有效地指导、规范课程建设实践。针对这一问... 在线课程是开放大学远程教学的特色,其质量优劣直接影响到开放大学的办学质量和办学声誉。提高课程质量,离不开科学有效的质量评价体系,然而,目前,我国开放大学课程质量评价发展相对滞后,难以有效地指导、规范课程建设实践。针对这一问题,以美国Quality Matters在线课程质量评价项目为研究对象,分析其在建立质量评价理念、评价标准、评价机制等方面的先进经验,为我国开放大学开展在线课程质量评价提供参考。 展开更多
关键词 在线课程 开放大学 质量评价
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以教师专业发展为核心的网络课程质量保证体系——美国Quality Matters核心竞争力及启示 被引量:28
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作者 钱玲 赵燕燕 《开放教育研究》 CSSCI 北大核心 2018年第5期30-38,72,共10页
网络课程质量保证是我国网络教育领域最受关注却一直难以解决的问题。网络课程的多元性与技术的快速发展使得对其进行系统评估和质量保证更难。本研究旨在通过对美国Quality Matters的深度探讨,分析其成为美国网络课程评价与质量保证领... 网络课程质量保证是我国网络教育领域最受关注却一直难以解决的问题。网络课程的多元性与技术的快速发展使得对其进行系统评估和质量保证更难。本研究旨在通过对美国Quality Matters的深度探讨,分析其成为美国网络课程评价与质量保证领军者的核心竞争力:独特的课程质量评价标准体系、专家同行评审机制、多元的认证项目和扎根于院校的理念。QM具有宽广的国际视野并以教育技术研究为坚实基础,可为我国网络课程评价的顺利开展提供新思路。 展开更多
关键词 网络课程 评价 质量保证 QM 美国
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基于统计特征的Quality Phrase挖掘方法 被引量:4
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作者 杨欢欢 赵书良 +2 位作者 李文斌 武永亮 田国强 《数据采集与处理》 CSCD 北大核心 2020年第3期458-473,共16页
Quality Phrase挖掘是从文本语料库中提取有意义短语的过程,是文档摘要、信息检索等任务的基础。然而现有的无监督短语挖掘方法存在候选短语质量不高、Quality Phrase的特征权重平均分配的问题。本文提出基于统计特征的Quality Phrase... Quality Phrase挖掘是从文本语料库中提取有意义短语的过程,是文档摘要、信息检索等任务的基础。然而现有的无监督短语挖掘方法存在候选短语质量不高、Quality Phrase的特征权重平均分配的问题。本文提出基于统计特征的Quality Phrase挖掘方法,将频繁N-Gram挖掘、多词短语组合性约束及单词短语拼写检查相结合,保证了候选短语的质量;引入公共知识库对候选短语添加类别标签,实现了Quality Phrase特征权重的分配,并考虑特征之间相互影响设置惩罚因子调整权重比例;按照候选短语的特征加权函数得分排序,提取Quality Phrase。实验结果表明,基于统计特征的Quality Phrase挖掘方法明显提高了短语挖掘的精度,与最优的无监督短语挖掘方法相比,精确率、召回率及F1-Score分别提升了5.97%,1.77%和4.02%。 展开更多
关键词 文本挖掘 quality Phrase 统计特征 候选短语 特征加权
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Incorporation of meat quality and use of ultrasound technology for swine genetic improvement programs 被引量:9
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作者 Tom J.BAAS 《华南农业大学学报》 CAS CSCD 北大核心 2005年第S1期88-98,共11页
Real-time ultrasound has been, and will continue to be, one of the most important tools in enhancing genetic improvement in the U.S. Recent advancements in the technology have allowed ultrasound to be used in evaluati... Real-time ultrasound has been, and will continue to be, one of the most important tools in enhancing genetic improvement in the U.S. Recent advancements in the technology have allowed ultrasound to be used in evaluating intramuscular fat in live animals. Together with other genetic improvement tools, ultrasound technology will offer seedstock producers the opportunity to select for improved IMF in potential breeding stock replacements and hence speed genetic progress for the improvement of this trait. After three generations of selection for IMF using real-time ultrasound in an Iowa State University study, the average EBV for select line pigs is 0.83% greater than for control line pigs. Selection for IMF has, however, resulted in slightly more backfat and less loin muscle area, and a trend toward more days to 114 kg in the select line compared to the control line. Carcass evaluation of a sample of pigs from each litter indicated a similar increase in IMF, increase in backfat, and reduction in loin muscle area for select line pigs. No differences were found for Hunter L* color, Minolta reflectance, and ultimate pH. 展开更多
关键词 SWINE meat quality intramuscular fat ultrasound technology
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Principal Component Analysis of Cooked Rice Texture Qualities 被引量:17
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作者 LIU Chenghai ZHENG Xianzhe DING Ningye 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第1期70-74,共5页
Texture qualities of cooked rice are comprised of many indexes with the complex relationship, so it is difficult to analyze and evaluate cooked rice. In this paper, the related indexes of texture properties were conve... Texture qualities of cooked rice are comprised of many indexes with the complex relationship, so it is difficult to analyze and evaluate cooked rice. In this paper, the related indexes of texture properties were conversed into the independent indexes of principal component based on the principal component analysis method. The results showed that the rice kernel types influenced the meanings of principal components indexes. For long and short rice, the first principal component was comprehensive index. But the second principal component was springiness for the short rice, while it was adhesiveness for long rice. Therefore, the first principal component can be used to express the quality of cooked rice with a few of indexes, and the rice type can be recognized according to the second principal component. 展开更多
关键词 cooked rice texture quality principal component analysis
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Effects of Probiotics on Growth, Pork Quality and Serum Metabolites in Growing-finishing Pigs 被引量:16
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作者 Liu Tian-yang Su Bin-chao +2 位作者 Wang Jia-li Zhang Chao Shan An-shan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第4期57-63,共7页
A total of 72 growing-finishing pigs(56 days old) were used to investigate the effects of dietary probiotics on growing performance, pork quality and serum metabolites. Using single factorial experiment design, pigs... A total of 72 growing-finishing pigs(56 days old) were used to investigate the effects of dietary probiotics on growing performance, pork quality and serum metabolites. Using single factorial experiment design, pigs were allotted to three groups(four pens/group and six pigs/pen). Diet treatments were a corn-soybean meal(control group) and a corn-soybean meal with 1% probiotics(probiotics group) or 80 mg kg-1colistin sulfate(antibiotics group). Pigs were slaughtered when pigs of the lightest averaged 90 kg(157 days of age). There was no difference(p&gt;0.05) in average daily gain or feed/gain, and the average daily feed intake of the antibiotics group was higher than that of the probiotics and the control groups(p&lt;0.05). Diet supplemented with probiotics reduced the drip loss and cooking loss of pork(p&lt;0.05). Dietary supplementation with probiotics significantly decreased the content of triglycerides, lowdensity lipoprotein and urea nitrogen in serum(p&lt;0.05), and increased the content of high-density lipoprotein in serum(p&lt;0.05). These results suggested improving effects of dietary probiotics on pork quality and serum metabolism in growing-finishing pigs. 展开更多
关键词 PROBIOTICS growing-finishing pig growth performance pork quality serum metabolite
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Correlation Between Physicochemical Properties and Eating Qualities of Rice 被引量:6
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作者 Qin Ke-xin Liu Lin-lin +2 位作者 Liu Tian-yi Cheng Wen-hong Shi Yan-guo 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第3期60-67,共8页
Correlation among physicochemical properties, which include amylose content, alkali spreading values, gel consistency, water absorption, expansion rate, solid content of rice-water, protein content and fat content, an... Correlation among physicochemical properties, which include amylose content, alkali spreading values, gel consistency, water absorption, expansion rate, solid content of rice-water, protein content and fat content, and eating qualities of six kinds of rice samples planted in Heilongjiang Province were studied. Correlation analysis showed that amylose content, water absorption and expansion rate were negatively correlated with eating qualities, yet gel consistency, alkali spreading values, solid content of rice-water and fat content were positively correlated with eating qualities. Among them, eating quality had an obvious correlation with amylose content and gel consistency, but no significant correlation with protein content. The regression equation, which described the relationship of the eating quality scores and physicochemical indexes, was Y=94.439–12.711X1–23.721X2–0.701X3+0.570X4+186.938X5(X1, X2, X3, X4 and X5 represented amylose content, water absorption, expansion rate gel, consistency and fat content). The single factor analysis of variance showed that six kinds of rice existed significant differences in quality category. 展开更多
关键词 RICE physicochemical property eating quality CORRELATION
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Energy Consumption by Rural Households in Northern Hunan 被引量:1
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作者 LI Lin,ZHOU Jin,ZHANG Guo-qiang(Research Center for Building Environment and Energy Saving,Hunan University,Changsha,Hunan 410082,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期182-185,共4页
This study was conducted to investigate the household energy consumption in rural districts in northern Hunan and to help explore the sustainable and ecological energy policy.Questionnaires were used to acquire the de... This study was conducted to investigate the household energy consumption in rural districts in northern Hunan and to help explore the sustainable and ecological energy policy.Questionnaires were used to acquire the details of energy consumption,and the electricity equivalent calculation was used in the energy statistics in four villages.The energy consumption in these four villages is influenced by the economic condition,geographic position and landform and the local custom.The traditional biomass energy and coal briquette are the primary energy source for cooking and heating,but they are used in a very low efficiency and result in poor IAQ.For sustainability,further measures should be taken to optimize the energy consumption with the efficient use of biomass energy,coal and electricity. 展开更多
关键词 structure AMOUNT RURAL ENERGY CONSUMPTION NORTHERN hunan
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Effects of Chitosan Coating on Disease Resistance and Storage Quality of Navel Orange Fruit 被引量:21
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作者 DENG Yu-yan MING Jian ZENG Kai-fang 《食品科学》 EI CAS CSCD 北大核心 2008年第11期656-661,共6页
In order to understand how chitosan affects disease resistance and quality of navel orange fruit(Citrussinensis L.osbeck)cv.Newhall after harvest,navel orange fruits were treated with 2 g chitosan/100 g solution for 1... In order to understand how chitosan affects disease resistance and quality of navel orange fruit(Citrussinensis L.osbeck)cv.Newhall after harvest,navel orange fruits were treated with 2 g chitosan/100 g solution for 1 min,and some fruits were taken out,dried naturally and inoculated with Penicillium italicum.Then,the fruits were stored at 20℃and 85%to 95%RH.Results indicated that the disease incidence and the lesion diameter in the chitosan-treated fruit are 72.72%and 90.19%,lower than those in control fruit on the 18^th day of incubation.The chitosan treatment maintains the soluble protein content,total phenolic and flavonoid level of navel orange fruit,which maybe involve in the maintenance of disease resistance of navel orange fruit.Treating navel orange fruit with 2 g chitosan/100 g solution effectively reduces the decrease in the content ofascorbic acid(AsA),water,titratable acidity(TA)and total soluble solids(TSS).These results suggested that the treatment with chitosan coating enhances the disease resistance and exhibits a potential for storage life extension of the navel orange fruit stored at ambient temperature. 展开更多
关键词 CHITOSAN navel orange FRUIT disease resistance quality
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Product design on the basis of fuzzy quality function deployment 被引量:2
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作者 Li Zhaoling Gao Qisheng Zhang Dongling 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1165-1170,共6页
In the implementation of quality function deployment (QFD), the determination of the target values of engineering characteristics is a complex decision process with multiple variables and multiple objectives that sh... In the implementation of quality function deployment (QFD), the determination of the target values of engineering characteristics is a complex decision process with multiple variables and multiple objectives that should trade off, and optimize all kinds of conflicts and constraints. A fuzzy linear programming model (FLP) is proposed. On the basis of the inherent fuzziness of QFD system, triangular fuzzy numbers are used to represent all the relationships and correlations, and then, the functional relationships between the customer needs and engineering characteristics and the functional correlations among the engineering characteristics are determined with the information in the house of quality (HoQ) fully used. The fuzzy linear programming (FLP) model aims to find the optimal target values of the engineering characteristics to maximize the customer satisfaction. Finally, the proposed method is illustrated by a numerical example. 展开更多
关键词 quality function deployment house of quality product design fuzzy optimization customer satisfaction
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不同培育方式朝鲜淫羊藿品质及土壤特性
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作者 侯会玲 李涵冰 +3 位作者 李艳霞 向光亿 张永刚 李晓宇 《东北林业大学学报》 北大核心 2026年第1期110-117,共8页
探究不同培育方式对朝鲜淫羊藿(Epimedium koreanum Nakai)品质的影响,并分析其与根际土壤特性之间的相关性,以丰富其生态种植理论,为高品质栽培技术提供科学依据。以野生抚育(WT)、林下仿生栽培(FP)和拟境栽培(SC)3种培育方式的朝鲜淫... 探究不同培育方式对朝鲜淫羊藿(Epimedium koreanum Nakai)品质的影响,并分析其与根际土壤特性之间的相关性,以丰富其生态种植理论,为高品质栽培技术提供科学依据。以野生抚育(WT)、林下仿生栽培(FP)和拟境栽培(SC)3种培育方式的朝鲜淫羊藿为对象,比较分析朝鲜淫羊藿品质、根际土壤理化性质及酶活性的动态变化和相互关系。结果表明:黄酮醇苷类及总黄酮等活性成分的质量分数由大到小总体表现为SC、FP、WT,且在7月下旬至8月下旬期间积累趋于稳定。相关性分析显示,土壤全钾与活性成分质量分数呈极显著正相关(P<0.01),速效磷与朝藿定B、总黄酮醇苷呈正相关(P<0.05);而有机质、全氮及土壤酶活性则与活性成分呈显著负相关(P<0.05)。综合实际生产效益,建议推广林下仿生栽培模式,并在土壤管理过程中采取“控氮、增磷钾”的施肥策略。 展开更多
关键词 朝鲜淫羊藿 培育方式 药材质量 土壤因子
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Effects of Dietary Protein and Temperature on Growth and Flesh Quality of Songpu Mirror Carp 被引量:2
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作者 Wang Chang-an Xu Qi-you +3 位作者 Zhao Zhi-gang Li Jin-nan Wang Lian-sheng Luo Liang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第2期53-61,共9页
The study was conducted to demonstrate the effects of dietary protein and water temperature on growth and flesh quality of Songpu mirror carp (Cyprinus carpio) at an initial weight (165.24±5.08) g. Practical ... The study was conducted to demonstrate the effects of dietary protein and water temperature on growth and flesh quality of Songpu mirror carp (Cyprinus carpio) at an initial weight (165.24±5.08) g. Practical diets were formulated to contain five protein levels (29.12%, 31.46%, 34.49%, 38.17%, and 40.13%), and each diet was randomly assigned triplicate groups of 15 fishes at three temperatures (18℃, 22℃, and 26℃) in the recirculation system. Fishes were fed twice daily to apparent satiation for 56 days. Results indicated that fishes had higher weight gain rate at 22℃ and 26℃ than that at 18℃ (P〈0.05), but there were no significant differences between 22℃ and 26℃ (P〉0.05). Based on the weight gain rate, dietary protein level 29.12% could meet the requirement of the body at 18℃, 22℃, or 26℃. Crude protein, crude lipid, moisture and ash of muscle had no significant differences among those treatments (P〉0.05). pH (after 24 h) of muscle was the highest at 18℃ and the lowest at 22℃ (P〈0.05), but no differences were observed among different protein level groups at each temperature (P〉0.05). No significant differences on shear force, water holding capacity, collagen, glycogen and lactate among all the treatments were found (P〉0.05). It was concluded that when C. carpio fed to apparent satiation, the growth mainly depended upon temperature. Dietary protein could not significantly affect flesh quality, but temperature significantly affected pH of muscles. A dietary protein level 29.12% could meet the requirement of the body at 18℃, 22℃, or 26℃. 展开更多
关键词 Songpu mirror carp flesh quality GROWTH PROTEIN TEMPERATURE
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Diagenesis and reservoir quality of the fourth member sandstones of Shahejie formation in Huimin depression,eastern China 被引量:5
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作者 张金亮 李德勇 江志强 《Journal of Central South University》 SCIE EI CAS 2010年第1期169-179,共11页
Petrographic analysis combined with various techniques, such as scanning electron microscopy and X-ray diffraction, was used to assess the timing of growth and original mineral cements, the controls on reservoir and r... Petrographic analysis combined with various techniques, such as scanning electron microscopy and X-ray diffraction, was used to assess the timing of growth and original mineral cements, the controls on reservoir and reservoir quality of the fourth member sandstones of Shahejie formation (Es4). The Es4 sandstones are mostly arkose and lithic arkose, rarely feldspathic litharenite, with an average mass fraction of quartz 51.6%, feldspar 33.8% and rock fragments 14.6% (Q51.6F33.8R14.6). They have an average framework composition (mass fraction) of quartz 57.10%, K-feldspar 5.76%, sodium-calcium feldspar 13.00%, calcite 5.77%, dolomite 5.63%, siderite 0.95%, pyrite 0.30%, anhydrite 0.04%, and clay mineral 11.46%. The diagenentic minerals typically include kaolinite, illite-smectite (I/S), illite, chlorite, authigenetic quartz and feldspar, and carbonate and pyrite. Es4 sandstone has undergone stages A and B of eodiagenesis, and now, it is experiencing stage A of mesodiagenesis. Reservoir quality is predominantly controlled by the mechanical compaction, for example, 45.65% of the original porosity loss is related to compaction. The original porosity loss related with cementation is only 26.00%. The reservoir quality is improved as a result of dissolution of feldspar, rock fragment and so forth. The porosity evolved from dissolution varies from 3% to 4%. 展开更多
关键词 sandstone diagenesis KAOLINITE reservoir quality compaction Huimin depression
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Quality evaluation of layerlike backfilling and flow pattern of backfill slurry in stope 被引量:11
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作者 彭欣 李夕兵 +1 位作者 张钦礼 王新民 《Journal of Central South University of Technology》 EI 2007年第4期580-583,共4页
Stability condition and quality evaluation formula of layerlike backfilling roof,Q≥C,where Q denotes is quality index depending on allowable compressive or tensile strength and integrity of backfilling,and C is the t... Stability condition and quality evaluation formula of layerlike backfilling roof,Q≥C,where Q denotes is quality index depending on allowable compressive or tensile strength and integrity of backfilling,and C is the technical index depending on mining method and backfilling technology,were inferred according to simply supported beam theorem.Technical treatment measures for instable backfilling roof,including optimum of appropriate filling materials and dosage for excellent flow property and reduction of backfill cost.It is proved that slope equation of backfill slurry in a stope to be filled is y=hexp[x2/(2σ)2)],where h is height of cone and σ2 is mean square,and that optimum drainage point of backfill slurry can be determined by the equation and sizes of stope.Case study indicates that the results can give a theoretical support for quality evaluation and control of layerlike backfilling. 展开更多
关键词 layerlike backfilling quality evaluation flow pattern simply supported beam
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Source and location mechanism for lode gold deposits hosted in metamorphic rocks in northeastern Hunan, China 被引量:1
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作者 LIU Liang ming,PENG Sheng lin,YANG Qun zhou (College of Resources, Environment and Civil Engineering, Central South University, Changsha 410083, China) 《Journal of Central South University of Technology》 2001年第2期108-113,共6页
For understanding the source and location mechanism of lode gold deposits hosted in metamorphic rocks in northeastern Hunan, the authors analyzed the REE (rare earth elements) in ores and their host rocks, metallogeni... For understanding the source and location mechanism of lode gold deposits hosted in metamorphic rocks in northeastern Hunan, the authors analyzed the REE (rare earth elements) in ores and their host rocks, metallogenic elements in host rocks near and distant from the ore bodies, and characteristics of ore controlling structures, and deduced their genetic implication. Their geochemical features of REE and metallogenic elements suggest that they are formed by mobilization of dispersed metallogenic materials in Lengjiaxi Group of Middle Proterozoic during deformation and metamorphism process, mainly in Wulingian period. From the attributes of ore controlling structures and regularity of location of gold metallization, it is concluded that the location of gold deposits is closely related to reverse shearing. Ore forming fluids are focused on the secondary faults and extension fractures of reverse shear zones of nearly EW strike by stress driven diffusion and seismic pumping. 展开更多
关键词 lode gold deposit LOCATION fluid focus seismic pump northeastern hunan
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