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Defect Dipole Thermal-stability to the Electro-mechanical Properties of Fe Doped PZT Ceramics
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作者 SUN Yuxuan WANG Zheng +5 位作者 SHI Xue SHI Ying DU Wentong MAN Zhenyong ZHENG Liaoying LI Guorong 《无机材料学报》 北大核心 2025年第5期545-551,I0009-I0010,共9页
The accepted doping ion in Ti^(4+)-site of PbZr_(y)Ti_(1–y)O_(3)(PZT)-based piezoelectric ceramics is a well-known method to increase mechanical quality factor(Q_(m)),since the acceptor coupled by oxygen vacancy beco... The accepted doping ion in Ti^(4+)-site of PbZr_(y)Ti_(1–y)O_(3)(PZT)-based piezoelectric ceramics is a well-known method to increase mechanical quality factor(Q_(m)),since the acceptor coupled by oxygen vacancy becomes defect dipole,which prevents the domain rotation.In this field,a serious problem is that generally,Qm decreases as the temperature(T)increases,since the oxygen vacancies are decoupled from the defect dipoles.In this work,Q_(m) of Pb_(0.95)Sr_(0.05)(Zr_(0.53)Ti_(0.47))O_(3)(PSZT)ceramics doped by 0.40%Fe_(2)O_(3)(in mole)abnormally increases as T increases,of which the Qm and piezoelectric coefficient(d_(33))at room temperature and Curie temperature(TC)are 507,292 pC/N,and 345℃,respectively.The maximum Qm of 824 was achieved in the range of 120–160℃,which is 62.52%higher than that at room temperature,while the dynamic piezoelectric constant(d_(31))was just slightly decreased by 3.85%.X-ray diffraction(XRD)and piezoresponse force microscopy results show that the interplanar spacing and the fine domains form as temperature increases,and the thermally stimulated depolarization current shows that the defect dipoles are stable even the temperature up to 240℃.It can be deduced that the aggregation of oxygen vacancies near the fine domains and defect dipole can be stable up to 240℃,which pins domain rotation,resulting in the enhanced Q_(m) with the increasing temperature.These results give a potential path to design high Q_(m) at high temperature. 展开更多
关键词 defect dipole temperature characteristic oxygen vacancy electro-mechanical property mechanical quality factor hardening doping
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Detection Research and Control Evaluation of Seam Roof Water Yield Property in Yulin-Hengshan Southern Mining Area 被引量:23
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作者 方刚 《矿业安全与环保》 北大核心 2017年第5期98-102,共5页
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Climate adaptive thermal characteristics of envelope of residential passive house in China 被引量:2
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作者 DUAN Meng-fan SUN Hong-li +2 位作者 WU Yi-fan WU Xiao-ying LIN Bo-rong 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第7期2317-2329,共13页
Passive house has been constructed in China on a large-scale over the past couple years for its great energy saving potential.However,research indicates that there is a significant discrepancy in energy performance fo... Passive house has been constructed in China on a large-scale over the past couple years for its great energy saving potential.However,research indicates that there is a significant discrepancy in energy performance for heating and cooling between passive houses in different climate zones.Therefore,this research develops a comparative analysis on the energy saving potential of passive houses with the conventional around China.A sensitivity analysis of thermal characteristics of building envelope(insulation of exterior walls and windows,and airtightness)on energy consumption is further carried out to improve the climate adaptability of passive house.Moreover,the variation of energy consumption under different heat gain intensity is also compared,to evaluate the effects of envelope thermal characteristics comprehensively.Results suggest that the decrease of exterior wall insulation leads to the greatest increase in energy consumption,especially in severe cold zone in China.However,the optimal insulation may change with the internal heat gain intensity,for instance,the decrease of insulation(from 0.4 to 1.0 W/(m^(2)·K))could reduce the energy consumption by 4.65 kW·h/(m^(2)·a)when the heat gain increases to 20 W/m^(2)for buildings in Hot Summer and Cold Winter zone in China. 展开更多
关键词 passive house envelope thermal characteristics climate adaptability heating and cooling energy consumption
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第9期I0031-I0031,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the fi eld of animal-origin foods,involving food mate... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the fi eld of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第7期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food mat... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product fl avor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第8期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the field of animal-origin foods,involving food mate... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第9期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food mat... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product fl avor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Effects of Variable Lighting Intensity on Growth Characteristics and Nutritional Quality of Hydroponically Grown Arugula(Eruca sativa Mill.)
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作者 Sun Ming-han Zhou Fu-jun +1 位作者 Liu He Zhao Jing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第1期85-96,共12页
Arugula(Eruca sativa Mill.),as an edible medicinal vegetable of peculiar flavor,is served as uncooked dish.The influence of variable lighting intensity(LI)on the growth characteristics and nutritional quality of hydro... Arugula(Eruca sativa Mill.),as an edible medicinal vegetable of peculiar flavor,is served as uncooked dish.The influence of variable lighting intensity(LI)on the growth characteristics and nutritional quality of hydroponically grown arugula was investigated by using light-emitting diodes(LEDs)to light the hydroponically grown arugula for a reference for industrialized arugula production.The dynamic demands of arugula for LI in the seedling stage,initial growth stage and vigorous growth stage were tested under two light quality conditions including a red/blue light ratio of 7:1 and a light/dark photoperiod of 12 h/12 h.Then,the curves of variable LI-induced changes in the growth indices of arugula in different development periods were drawn.Next,the influence of variable LI on the growth characteristics and nutritional quality of arugula was investigated by measuring the dry/fresh weight ratio,chlorophyll content,vitamin C content and soluble protein content.Variable LI significantly increased the height,stem diameter,leaf width,dry/fresh weight ratio,chlorophyll content and soluble protein content of arugula plant.Plant height,stem diameter,dry/fresh weight ratio,chlorophyll content and soluble protein content were the highest in the group exposed to LI of 200,300 and 300μmol•m^(-2)•s^(-1)during the seedling stage,initial growth stage and vigorous growth stage,respectively.The greatest leaf width was achieved at LI of 100,250 and 350μmol•m^(-2)•s^(-1),respectively.High intensity LI markedly repressed the synthesis of vitamin C. 展开更多
关键词 arugula LED lighting intensity growth characteristics nutritional quality plant factory
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第20期I0021-I0021,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第12期I0022-I0022,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第10期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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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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发芽糙米特征营养、食味品质提升及功能性评价研究进展 被引量:1
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作者 任传英 洪滨 +8 位作者 张珊 袁迪 冯俊然 山珊 张竞一 管立军 李波 黄文功 卢淑雯 《食品科学》 EI CAS 北大核心 2025年第1期284-292,共9页
发芽糙米作为一种全谷物,保留了完整的皮层和胚,集中了大部分营养素和功能性活性物质,但由于皮层纤维结构致密,蒸饭过程中阻碍了吸水速率、吸水量和淀粉糊化,与大米相比,其蒸煮性和食用品质较差,且难以同煮同熟,因此一直以来未被广大消... 发芽糙米作为一种全谷物,保留了完整的皮层和胚,集中了大部分营养素和功能性活性物质,但由于皮层纤维结构致密,蒸饭过程中阻碍了吸水速率、吸水量和淀粉糊化,与大米相比,其蒸煮性和食用品质较差,且难以同煮同熟,因此一直以来未被广大消费者接受。本文综述糙米发芽的生理代谢反应及发芽过程中营养成分、活性成分和食味品质的变化,总结发芽糙米胁迫富集γ-氨基丁酸(γ-aminobutyric acid,GABA)技术和发芽糙米的功能特性研究现状。糙米发芽过程中,多种生物活性物质在酶促反应下富集,尤其是特征成分GABA含量显著提升。多种逆境胁迫均可通过改变Ca^(2+)、H^(+)或底物水平促进GABA富集,一些预处理技术可进一步提升发芽糙米的食味品质。GABA与其他营养成分和活性成分发挥协同作用,赋予发芽糙米抗高血脂、抗高血糖、保护心脏、改善睡眠、抗炎和抗氧化等一系列功效与作用。 展开更多
关键词 发芽糙米 特征营养 食味品质 功能性
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构建房地产发展新模式的现实动因、实践探索与改革进路 被引量:1
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作者 潘文轩 《西南金融》 北大核心 2025年第4期3-15,共13页
构建房地产发展新模式是实现房地产高质量发展、创造高品质居住生活的时代要求。根据房地产发展模式五要素框架,房地产发展原模式向新模式的转型涵盖了住房属性定位、住房需求行为、住房供给体系、房企经营模式、住房基础性制度五方面... 构建房地产发展新模式是实现房地产高质量发展、创造高品质居住生活的时代要求。根据房地产发展模式五要素框架,房地产发展原模式向新模式的转型涵盖了住房属性定位、住房需求行为、住房供给体系、房企经营模式、住房基础性制度五方面的适应性变革。在新形势下,房地产发展原模式难以持续运行,其弊端和负面影响愈发突出,不适应高质量发展和高品质生活的需要,亟待加快构建房地产发展新模式。近年来,构建房地产发展新模式的实践探索初显成效但仍有局限性。今后,要加强改革的系统集成,继续坚持房住不炒定位,平衡住房的经济属性与社会属性,支持居民自住购房及租房需求,健全商品房与保障房并行、租售均衡发展、多主体参与的住房供给体系,推动房企向综合运营商转变以及往品质化方向发展,进一步完善住房用地、金融、财税、保障、管理等方面的住房基础性制度,实现房地产发展原模式向新模式的全面转换。 展开更多
关键词 房地产 高质量发展 住房供给 住房需求 住房保障 房地产企业 住房制度 租购并举
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交错布种下氮肥减施对花生根系特性及产量品质的影响 被引量:1
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作者 王婧 赵世玉 +7 位作者 徐爽 谢畅 蒋春姬 赵新华 刘喜波 钟超 于海秋 王晓光 《沈阳农业大学学报》 北大核心 2025年第2期22-33,共12页
[目的]针对辽宁省花生生产上氮肥施用量过大,导致氮肥利用率低、产量和品质下降的现状,探究交错布种下氮肥减施对花生根系特性及产量品质的影响,以期明确辽宁地区单垄交错布种条件下花生最佳氮肥减施量,为当地的花生生产提供理论依据和... [目的]针对辽宁省花生生产上氮肥施用量过大,导致氮肥利用率低、产量和品质下降的现状,探究交错布种下氮肥减施对花生根系特性及产量品质的影响,以期明确辽宁地区单垄交错布种条件下花生最佳氮肥减施量,为当地的花生生产提供理论依据和参考。[方法]试验于2019-2020年在沈阳农业大学进行,以青花6号为试材,采用大田随机区组设计,设置5个氮肥用量水平,T0(不施氮肥)、T1(纯氮82.5 kg·hm^(-2),大田常规施氮量)、T2(纯氮70 kg·hm^(-2),氮减施15%)、T3(纯氮62 kg·hm^(-2),氮减施25%)、T4(纯N54 kg·hm^(-2),N减施35%),研究氮肥减施对花生根系形态、根瘤特性及产量品质的影响。[结果]氮肥适量减施能够有效促进单垄交错布种花生根系形态的优化,T2处理可显著增加花生的根长、根表面积和根平均直径,并在生育期内保持较高的根系活力。通过对花生根瘤超显微结构分析得出,氮肥减施能促进类菌体增大并产生脂质体。与T0相比,施氮肥提高了花生荚果产量,增产幅度为3.76%~9.74%。不同氮肥减施量对产量的影响不同,其中T2处理下获得最高产量,两年平均比T1增产2.17%,而T3处理平均比T1减产0.58%。氮肥减施对花生籽仁品质的影响不显著。[结论]氮减施15%(T2)时有利于花生根系生长,增产效果最好,为最佳氮肥减施模式。 展开更多
关键词 花生 氮肥减施 根系形态 根瘤特性 产量 品质
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葡萄秸秆复合有机肥对设施黄瓜产量、品质及土壤特性的影响 被引量:1
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作者 唐艳领 马凯 +9 位作者 米国全 荆艳彩 蔡毓新 宋策 王腾起 李晓辉 王坐京 张英 牛莉莉 黄怡 《中国瓜菜》 北大核心 2025年第5期108-115,共8页
为减少化肥施用量、提高土壤养分的可持续性,探究葡萄秸秆复合有机肥等量替代化肥对黄瓜生长发育及土壤特性的影响,以黄瓜博杰618为材料,设置了不施肥(CK)、单施化肥(CF)、有机肥替代化肥(F1:替代10%N、25%P、18%K,F2:替代20%N、50%P、3... 为减少化肥施用量、提高土壤养分的可持续性,探究葡萄秸秆复合有机肥等量替代化肥对黄瓜生长发育及土壤特性的影响,以黄瓜博杰618为材料,设置了不施肥(CK)、单施化肥(CF)、有机肥替代化肥(F1:替代10%N、25%P、18%K,F2:替代20%N、50%P、36%K,F3:替代30%N、75%P、54%K)5个试验处理,重点对比不同施肥处理对黄瓜产量、品质及土壤特性的影响。结果表明,与CK相比,F2处理显著增产19.6%,667 m^(2)产量最高,为9576.49 kg。与CF相比,各有机肥替代处理的可溶性固形物含量显著增加了1.10%~3.88%,维生素C含量增加了3.64%~11.56%。各施有机肥处理的土壤全氮全磷有机质含量显著高于CK。与CK相比,F2、F3处理可显著降低土壤硝酸还原酶活性,提高土壤脲酶、蔗糖酶活性。与CF相比,F1、F2和F3处理更能增加土壤中细菌和放线菌的数量。对黄瓜产量、品质及土壤养分进行主成分分析后,各处理得分从高到低为F2>F3>F1>CF>CK。综上所述,F2处理相比于其他处理组表现最优,能提高黄瓜品质及产量,增加了土壤养分并提高了土壤酶活性。研究结果为黄瓜减肥增效、绿色生产提供了理论依据和技术支撑。 展开更多
关键词 黄瓜 葡萄秸秆复合有机肥 产量 品质 土壤特性
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淮北平原浅层地下水化学特征及水质动态研究 被引量:1
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作者 朱春芳 龚建师 +5 位作者 檀梦皎 陶小虎 周锴锷 王赫生 李亮 秦曦 《水文地质工程地质》 北大核心 2025年第3期56-67,共12页
浅层地下水是淮北平原最重要的农业用水供水水源,水质状况广受关注。文章采用数理统计、舒卡列夫分类、Piper三线图和水质综合评价得出淮北平原浅层地下水化学特征及水质现状,运用Gibbs图和离子比值关系分析了水化学物质来源,应用主成... 浅层地下水是淮北平原最重要的农业用水供水水源,水质状况广受关注。文章采用数理统计、舒卡列夫分类、Piper三线图和水质综合评价得出淮北平原浅层地下水化学特征及水质现状,运用Gibbs图和离子比值关系分析了水化学物质来源,应用主成分分析法筛选影响地下水质量的典型因子并推演时空演变规律。结果表明:淮北平原浅层地下水多为弱碱性淡水,p H值6.6~8.6,溶解性总固体192~5302 mg/L,主要水化学类型共8类,主要阴离子为HCO_(3)^(-),阳离子为Na^(+)、Ca^(2+),地下水质量以Ⅳ类水为主;水岩作用主要受硅酸盐岩-碳酸盐岩岩石风化作用影响,从上游淮北平原到中游淮北平原,岩石风化溶解的水岩作用由碳酸盐岩向硅酸盐岩再向蒸发盐岩演化。通过主成分分析选取溶解性总固体、耗氧量、硝酸盐作为典型因子研究水质动态演化规律,淮北平原浅层地下水质量在2010—2021年经历了明显好转后略有下降,但典型因子的表现不尽相同;受原生地质环境影响,淮北平原浅层地下水可溶物质总量趋向于面状集中分布,高值点增多且大多分布于中游淮北平原,氧化还原条件从还原环境向氧化环境演变,2010—2018年农业活动等人为污染在上游淮北平原局部加重,但在2018年后得到明显改善。研究结果可为淮北平原浅层地下水污染防治、地下水资源保护提供支撑。 展开更多
关键词 淮北平原 浅层地下水 水化学特征 水质 主成分分析
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中国新质生产力发展水平区域评价与空间关联网络特征 被引量:6
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作者 马大晋 吴旭辉 张博文 《财经论丛(浙江财经大学学报)》 北大核心 2025年第5期17-27,共11页
本文运用加入时间变量的熵权法、修正引力模型和社会网络分析法,探索中国各区域2010—2022年新质生产力发展水平及区域间的互动关系。研究结果发现,中国新质生产力发展水平逐年提升,但东西差距、南北差距逐渐扩大,呈“东高西低,南强北... 本文运用加入时间变量的熵权法、修正引力模型和社会网络分析法,探索中国各区域2010—2022年新质生产力发展水平及区域间的互动关系。研究结果发现,中国新质生产力发展水平逐年提升,但东西差距、南北差距逐渐扩大,呈“东高西低,南强北弱”的分布格局;区域间空间关联网络的整体密度较小,但联通性和稳定性较好;净溢出板块和经纪人板块集中在中西部和东北地区,净受益板块和双向溢出板块集中在东部地区,且净受益板块对其余三个板块的虹吸效应较强,但板块间、板块内成员的互动关系随新质生产力发展水平的提升而持续改善。上述结论对因地制宜制定区域新质生产力发展策略、缩小区域发展差距、推动中国经济整体高质量发展具有一定的现实意义。 展开更多
关键词 新质生产力 区域差异 空间关联网络特征 区域协调发展 科技创新
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不同配方沼渣基质对黄瓜育苗质量的影响 被引量:1
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作者 李金霞 陈思瑾 +4 位作者 李娟 陈年来 孙小妹 方三叶 王昱 《中国土壤与肥料》 北大核心 2025年第4期229-237,共9页
开展以沼渣为主要原料的新型有机栽培基质的研究对高效利用沼气发酵残余物和农业可持续发展具有重要现实意义。将沼渣与泥炭、蛭石和珍珠岩按一定粒径和质量比混配成4种复合基质,以商品基质为对照CK,以黄瓜种子为试验材料,研究混配基质... 开展以沼渣为主要原料的新型有机栽培基质的研究对高效利用沼气发酵残余物和农业可持续发展具有重要现实意义。将沼渣与泥炭、蛭石和珍珠岩按一定粒径和质量比混配成4种复合基质,以商品基质为对照CK,以黄瓜种子为试验材料,研究混配基质的理化性质及其对黄瓜幼苗生长的影响。结果表明:(1)不同配方沼渣基质容重范围为0.19~0.22 g/cm^(3),均极显著低于CK;电导率范围为1.58~2.15 mS/cm,GS2、GS3、GS4处理的电导率均显著高于CK;总孔隙度为60.30%~68.65%;混配基质的pH值和铵态氮含量均显著高于CK,有机质和有效磷含量分别表现为GS4>GS3>GS1>CK>GS2和GS2>GS1>GS3>CK>GS4。(2)不同配方沼渣基质黄瓜幼苗的株高、叶面积、根体积、地上鲜重、地下干重、总鲜重、总干重等均高于CK,其中GS3处理的出苗率、株高、茎粗、地上鲜重、总干重、壮苗指数和生长函数(G)值均高于其他处理,表现出明显的生长优势。(3)主成分分析结果表明幼苗株高、茎粗、叶面积、地上鲜重与铵态氮、有效磷、pH值、电导率正相关,根体积与气水比、铵态氮正相关,地下鲜重与与持水孔隙度和持水能力负相关,Mantel分析显示壮苗指数和G值主要受铵态氮、容重、总孔隙度、持水能力和电导率的影响。(4)通过综合评价可知,GS3处理综合评价指数最高(0.61),黄瓜幼苗综合生长状况最佳。综上,沼渣部分替代泥炭进行黄瓜育苗可以有效提高黄瓜幼苗质量,G3配方处理黄瓜穴盘苗质量最佳。 展开更多
关键词 沼渣基质 理化性质 黄瓜 生长特性 幼苗质量
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干制方式对九叶青花椒干燥特性和品质的影响 被引量:2
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作者 饶胜其 徐富慧 +4 位作者 伏晴晴 梅小飞 刘美琴 杨振泉 王智荣 《食品科学技术学报》 北大核心 2025年第1期156-170,共15页
干制是花椒采后重要的加工处理环节之一,对花椒的品质有较大影响。探究了自然阴干(shade drying,SD)、热风干燥(hot air drying,HAD)、热泵干燥(hot pump drying,HPD)、微波干燥(microwave drying,MD)、冷冻干燥(freeze drying,FD)及汽... 干制是花椒采后重要的加工处理环节之一,对花椒的品质有较大影响。探究了自然阴干(shade drying,SD)、热风干燥(hot air drying,HAD)、热泵干燥(hot pump drying,HPD)、微波干燥(microwave drying,MD)、冷冻干燥(freeze drying,FD)及汽蒸预处理(pretreatment by steaming,PS)结合5种干制方式的复合处理对九叶青花椒干燥特性和品质的影响。结果表明,Logarithimc和Weibull模型对几种方式下青花椒水分比随时间的变化规律拟合度较好。PS能有效抑制叶绿素的降解,但会显著降低挥发油含量。FD和PSFD能较好地保留青花椒中的叶绿素、麻味物质、总酚和总黄酮,但会导致极低的破壳率和挥发油含量。MD和PSMD的干燥速率最高,仅需约30 min即能完成干制过程,且保留了较高含量的麻味物质,但MD和PSMD处理的青花椒的色泽和形态较差。SD和HAD处理的青花椒的色泽和植物化学成分含量总体上都处于较低水平;而PS和HPD复合处理的青花椒色泽与市售一级青花椒较为接近,其挥发油(4.00 mL/100 g)、麻味物质(60.21 mg/g)、总酚(31.81 mg/g)和总黄酮(93.32 mg/g)含量均处于较高水平。干燥方式对青花椒的品质具有显著影响,破壳率和D-柠檬烯、麻味物质、总黄酮及叶绿素a的含量是影响不同干制青花椒品质差异的主要因素;各种干制青花椒综合得分排序前6位的依次为PSF D-青花椒、F D-青花椒、PSHP D-青花椒、HP D-青花椒、PSM D-青花椒和M D-青花椒。可根据干制成本和产品用途,选择适宜的青花椒干燥方法。 展开更多
关键词 青花椒 干制方式 汽蒸预处理 干燥特性 品质
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