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Effects of formal credit on pastoral household expense: Evidence from the Qinghai-Xizang Plateau of China

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Journal of Integrative Agriculture 2024年第5期23卷 1774-1785页

作者： yan Zhang Yi Huang Fan Zhang zeng Tang State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020China

Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'*** pastoral China,formal financial institutions are gradually ***,a limited understanding remains of how formal credit affects herders'household *** on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive *** results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal *** credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth ***,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household ***,this study suggests that policies should improve herders'accessibility to formal credit.

关键词： formal credit herders expense Qinghai-Xizang Plateau

Are microbes and metabolites influencing the parental consumption of nestlings’feces in gray-backed shrikes?

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Current Zoology 2022年第6期68卷 667-678页

作者： Jie HU Jingyuan zeng Yurou SHI Sen song School of Life Sciences Lanzhou UniversityLanzhou730000China

The behavioral video recordings of the gray-backed shrike Lanius tephronotus revealed that parent birds eat the feces produced by their nestlings.“Parental nutrition hypothesis”attributes the origin of this behavior to nutrition-recovery and cost-saving,***,the presence of usable nutrients in the nestlings’feces is unknown because of traditional *** this study,we analyzed all the metabolites and the variations in the diversity and content of microbes in the feces of gray-backed shrike *** aimed to report the changes in microbes and metabolites with the age of nestlings and point out that the parent birds that eat the feces may gain potential nutrition *** results showed that the relative abundances of Proteobacteria,Firmicutes,and Bacteroidota,changed significantly when the nestlings were 6 days *** relative abundances of 6 probiotics,which are involved in digestion,metabolism,and immunity-related physiological functions,decreased in the nestlings’feces gradually with age;therefore,these probiotics may be obtained by parent birds upon ingestion of the feces of young *** the metabolites that were detected,20 were lipids and some had a role in anti-parasitic functions and wound healing;however,their relative contents decreased with *** beneficial substances in the nestlings’feces may stimulate the parents to swallow the ***,there were many aromatic metabolites in the newly hatched nestlings’feces,but the content of bitter metabolites increased as they grew ***,our results are in accordance with the nutritional hypothesis.

关键词： feces disposal metabolite microbiota nestlings probiotics

Experimental study on the effects of sediment size and porosity on contaminant adsorption/desorption and interfacial diffusion characteristics

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Journal of Hydrodynamics 2013年第1期25卷 20-26页

作者： FAN Jing-yu HE Xiao-yan WANG Dao-zeng Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

The joint effects of the sediment size and porosity on the contaminant adsorption/desorption and interfacial diffusion characteristics were experimentally investigated. The adsorption of Phosphorus （P） on the natural and artificial sediment suspensions was measured with respect to the P adsorption isotherms and kinetics in the experiment. The obtained adsorption isotherms for different grain-sized sediment suspensions fit well with the Langmuir equation, dependent on the initial aqueous concentration and sediment content. The P kinetic adsorption behaviors for cohesive fine-grained and non-cohesive coarse-grained sediment suspensions clearly show the size-dependent feature. On the other hand, the P kinetic release feature of a porous sediment layer is affected by not only the direct desorption of the uppermost sediments, but also the diffusivity in the pore-water within the underlying sediment layer, characterized by the sediment size and porosity, respectively. Furthermore, the temporal contaminant release from the permeable sediment layer into the overlying water column increases with the increasing flow velocity, while this enhancement in mediating the interfacial diffusion flux is somewhat insignificant in an immediate release stage, largely due to the resistance of the diffusive boundary layer on the hydrodynamic disturbance.

关键词： sediment contaminant adsorption desorption interfacial diffusion

The Mobility of Threadedα-Cyclodextrins in PR Copolymer and Its Influences on Mechanical Properties

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Chinese Journal of Polymer Science 2017年第6期35卷 752-763页

作者： Zhi yan 叶霖 Ai-ying Zhang zeng-guo Feng School of Materials Science and Engineering Beijing Institute of Technology Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications

The methylated polyrotaxane （MePR） copolymer was prepared via the methylation of hydroxyl of threaded α-cyclodextrin （α-CDs） in polyrotaxane （PR） copolymer by CH3I/NaH. Its structure was characterized by GPC, IR and NMR. The WXRD and TGA measurements showed the destruction of channel-like crystalline structure in MePR copolymer. The sliding of threaded α-CDs along PEG axis in PR and MePR copolymers was demonstrated by their dielectric spectra that also evidenced the presence of rotating of threaded α-CDs around PEG axis in MePR eopolymer. The frequent and vigorous molecular mobility in MePR and PR copolymers was also verified by dynamic mechanical analysis （DMA） and rheological measurement, which was possibly assigned to the sliding and rotating of threaded α-CDs. DMA and rheological results showed that the mobility of α-CDs could simultaneously strengthen and toughen PR copolymer proved by stress-stain curves. In this paper, we report the CD mobility in PR and MePR copolymers. The macroscopic behaviors of PR copolymer, such as mechanical properties in solid state, were also found to be benefited from CD mobility.

关键词： PR copolymer Methylation CD mobility Dielectric measurement Mechanical property

The development and application of dual-comb spectroscopy in analytical chemistry

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Chinese Chemical Letters 2023年第1期34卷 39-44页

作者： Ziheng Wei Xinyi Ren Ming yan Hulie zeng Department of Pharmaceutical Analysis School of PharmacyFudan UniversityShanghai 201203China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

Analytical chemistry plays an important role in the qualitive and quantitative analysis for molecules in the various circumstances,especially for the high-resolution *** dual-comb spectroscopy(DCS)technology with the characteristics of high resolution,high sensitivity and instantaneous sampling exhibited a great potential in high-resolution in-situ spectral methods and has been active in the fields of spatial ranging,air composition analysis,reaction monitoring and so *** this review,we will summarize the principle of DCS according to the different wavelength coverage and overview the applications of DCS in analytical chemistry.

关键词： Dual-comb spectroscopy Infrared spectrum Raman spectrum Spectral analysis Gas detection

Chilling rather than photoperiod controls budburst for gymnosperm species in subtropical China

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Journal of Plant Ecology 2022年第1期15卷 100-110页

作者： Yuan-Qi Pan Xiu zeng Wen-De Chen Xin-Ran Tang Kui Dai yan-Jun Du Xi-Qiang song College of Tourism and Urban-Rural Planning Chengdu University of TechnologyChengdu 610059China College of Tropical Crops Hainan UniversityHaikou 570228China Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants(Ministry of Education) College of ForestryHainan UniversityHaikou 570228China

The mechanisms regulating spring phenology have been extensively studied in angiosperm ***,given that gymnosperms and angiosperms diverged 300 million years ago,phenology may be triggered by different cues in gymnosperm *** regulatory mechanisms of phenology in subtropical regions remain largely *** combination,it remains untested whether subtropical gymnosperm species have chilling requirements and are *** conducted a climate chamber experiment with three chilling and three photoperiod treatments to investigate budburst during an 8-week forcing *** tested whether budburst of eight gymnosperms species(Cryptomeria japonica,Cunninghamia lanceolata,Cupressus funebris,Ginkgo biloba,Metasequoia glyptostroboides,Pinus massoniana,Pseudolarix amabilis and Podocarpus macrophyllus)was photoperiod sensitive or has strong chilling requirements and whether photoperiod or chilling was more important for advancing *** advanced budburst and increased the percentage of budburst for gymnosperm *** species required moderate chilling days to advance ***,the forcing requirement for gymnosperm species was higher than that for angiosperms in the same forest,suggesting that gymnosperms may need more cumulative forcing to initiate budburst than do *** with temperate gymnosperm species in Germany(194-600℃days),the subtropical species studied here had a much higher forcing requirement(814-1150℃days).The effects of photoperiod were minor,suggesting that chilling outweighs photoperiod in advancing budburst of gymnosperm species in this subtropical *** results reveal that increased winter temperatures with continued global warming may impact not only angiosperms but also gymnosperms,leading to their delayed spring budburst.

关键词： chilling requirement climate change forcing requirement Gutianshan spring phenology twig cutting experiment

Enhancement of adjustable localized surface plasmon resonance in ZnO nanocrystals via a dual doping approach

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Science Bulletin 2017年第10期62卷 693-699页

作者： Yusufkadie Yibi Jiawei Chen Jie Xue Jizhong song Haibo zeng Ministry of Industry and Information Technology of the China Key Laboratory of Advanced Display Materials and Devices Institute of Optoelectronics & Nanomaterials Collegeof Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China

Recently, the localized surface plasmon resonance （LSPR） concept was expanded from noble metals to doped semiconductor nanocrystals （NCs）. However, the strengthening of the intrinsically very weak LSPR in NCs remains a great challenge for its applications in optics, electronics and optoelectronics fields. In this work, we report on the remarkable strengthening and controllability of LSPR in ZnO through a dual-doping strategy. First, high quality In-doped ZnO （IZO） NCs with intense LSPR were synthesized by a simple single-pot method. Importantly, the LSPR can be tuned by simply adjusting the concentration of In dopant, as well as by UV light irradiation （photo-induced doping）. The pattern of electricity of an IZO NC film matches the shift of LSPR independent of dopant concentration. The UV light irradiation clearly enhanced the electrical properties of the films （350 fl/sq） due to increase carrier density explained by LSPR and confirmed by X-ray photoelectron spectroscopy, The IZO NCs can be easily dispersed in various organic solvents and serve as inks for assembling uniform films via solution processes. These IZO NC ink is promising for application in next-generation solution-based field effect transistors and other optoelec- tronic devices.

关键词： Doped zinc oxide Colloidal nanocrystals LSPR Electrical properties UV treatment Ink

Improving Smoothing Efficiency of Rigid Conformal Polishing Tool Using Time-Dependent Smoothing Evaluation Model

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Photonic Sensors 2017年第2期7卷 171-181页

作者： Chi song Xuejun ZHANG Xin ZHANG Haifei HU Xuefeng zeng Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Key Laboratory of Optical System Advanced Manufacturing Technology Chinese Academy of Sciences Changchun 130033 China University of Chinese Academy of Sciences Beijing 100049 China

A rigid conformal （RC） lap can smooth mid-spatial-frequency （MSF） errors, which are naturally smaller than the tool size, while still removing large-scale errors in a short time. However, the RC-lap smoothing efficiency performance is poorer than expected, and existing smoothing models cannot explicitly specify the methods to improve this efficiency. We presented an explicit time-dependent smoothing evaluation model that contained specific smoothing parameters directly derived from the parametric smoothing model and the Preston equation. Based on the time-dependent model, we proposed a strategy to improve the RC-lap smoothing efficiency, which incorporated the theoretical model, tool optimization, and efficiency limit determination. Two sets of smoothing experiments were performed to demonstrate the smoothing efficiency achieved using the time-dependent smoothing model. A high, theory-like tool influence function and a limiting toolspeed of 300 RPM were obtained.

关键词： Optics design and fabrication optics fabrication polishing

Preparation and immunogenicity of tag-free recombinant human eppin

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Asian Journal of Andrology 2011年第6期13卷 889-894页

作者： Jie Zhang Xin-Liang Ding zeng-Hui Bian yan-Kai Xia Shou-Lin Wang Ling song Xin-Ru Wang School of Radiation Medicine and Public Health Medical College of Soochow University Suzhou 215123 China Department of Public Health Wuxi Center for Disease Prevention and Control Wuxi 214023 China Municipal Center for Disease Control and Prevention Nanjing 210003 China Key Laboratory of Reproductive Medicine Institute of Toxicology Nanjing Medical University Nanjing 201129 China

Human epididymal protease inhibitor （eppin） may be effective as a male contraceptive vaccine. In a number of studies, eppin with an engineered His6-tag has been produced using prokaryotic expression systems. For production of pharmaceutical-grade proteins for human use, however, the His6-tag must be removed. This study describes a method for producing recombinant human eppin without a His6-tag. We constructed plasmid pET28a （＋）-His6-tobacco etch virus （TEV）-eppin for expression in Escherichia coli. After purification and refolding, the fusion protein His6-TEV-eppin was digested with TEV protease to remove the His6-tag and was further purified by NTA-Ni2＋ affinity chromatography. Using this procedure, 2 mg of eppin without a His6-tag was isolated from 1 I of culture with a purity of 〉95%. The immunogenicity of the eppin was characterized using male Balb/c mice.

关键词： Eppin immunogenicity male contraception recombinant protein preparation tag-free