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Effect of the Grain for Green Project on freshwater ecosystem services under drought stress

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Journal of Mountain Science 2022年第4期19卷 974-986页

作者： HAN Hui-qing yang Jian-qiang liu Yue ZHANG Ying-jia WANG jun-wen College of Architecture and Urban Planning Guizhou Institute of TechnologyGuiyang 550003China College of Economics and Management Guizhou Institute of TechnologyGuiyang 550003China

The Grain for Green Project(GGP) is an important measure for the prevention of sloping farmland and the restoration of natural *** project has been critical to the restoration of ecological environments in western China. However,the effect of the GGP on freshwater ecosystem services under extreme climates remains unclear. Thus, taking the middle and upper reaches of the Wujiang River Basin in western China as an example, this study assessed the variation of three freshwater ecosystem services(e.g., water yield, soil retention and nutrient retention) impacted by the GGP under drought stress by employing the Integrated Valuation of Ecosystem Services and Tradeoffs(In VEST) model. In addition,the trade-off/synergistic relationship between three freshwater ecosystem services was analyzed based on the Pearson correlation coefficient. As revealed from the results, the effect of the GGP on the water yield and nutrient retention under drought stress was significantly higher than that on the soil *** the increase in the drought degree, the variation rate of the water yield and nutrient retention impacted by the GGP increased, whereas that of the soil retention decreased. The GGP in droughts of different seasons resulted in a significant heterogeneity in the changes of three freshwater ecosystem services. The correlation coefficients between the water yield and soil retention as well as that between the water yield and the nutrient retention increased, and the correlation coefficients declined between soil and nutrient retention under different drought degrees following the GGP. Unlike for the summer drought case, there were no significant changes in the correlation coefficients between three freshwater ecosystem services in spring, autumn and winter droughts. The results suggest that the amount of farmland converted to shrubland should be regulated to reduce the trade-off intensity between freshwater ecosystem services. In addition, food security and e

关键词： Grain for Green Project Freshwater ecosystem services Drought Spatial pattern Tradeoff and synergy

Solid phase synthesis of peptide–siRNA conjugates containing disulfde bond unit

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Chinese Chemical Letters 2013年第10期24卷 873-876页

作者： Xiao-Feng Wang Xian-Tao yang Yue Chen yang liu Lang Zou Zhen-jun yang Li-He Zhang State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University

A disulfide-modified nucleoside was designed and synthesized. After loading the modified nucleoside on controlled pore glass （CPG）, solid phase synthesis strategy was used to prepare peptide-oligonucleotide conjugates （N-3＇） containing disulfide bond unit. The 3＇-sense strand peptide-siRNA conjugate （VII） maintained good gene silencing activity, while that of the 3＇-antisense strand conjugate decreased somewhat. And the sense strand off-target effect of VII decreased remarkably.

关键词： siRNA Solid synthesis Disulfide bond Peptide Conjugate

Accurate analysis of limiting human dose of non-lethal laser weapons

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Defence Technology（防务技术） 2022年第4期18卷 678-688页

作者： Chen-yang Lyu Ren-jun Zhan College of Equipment Management and Support Chinese People’s Armed Police Force Engineering UniversityXi’an710086ShaanxiChina

In order to maximize the lethality and reversibility of the non-lethal laser weapons(NLLW) at the same time and thus provide a theoretical basis for the R&D of laser weapons in the future,this paper accurately analyzed the limiting biological dose of irreversible damage to human skin caused by the ***,based on the burn theory in medicine and the actual tactical background,this paper redefines the evaluation criteria of the limiting laser dose of NLLW to the human ***,on the basis of anatomical knowledge,a 5-layer finite element model(FEM) of superficial skin is proposed,constructed and verified,which can accurately describe the limiting reversible *** on the optimized Pennes bioheat transfer equation,the diffusion approximation theory,the modified Beer-Lambert law,the Arrhenius equation,and combined with dynamic thermophysical parameters,this paper highly restored the temperature distribution and accurately solved the necrotic tissue distribution inside the human skin irradiated by 1064 nm ***,it is concluded that the maximum human dose of the1064 nm NLLW is 8.93 J/cm^(2),8.29J/cm^(2),and 8.17 J/cm^(2) when the light spots are 5 mm,10 mm and15 mm,respectively,and the corresponding output power of the weapon is 46.74 W,173.72 W and384.77 ***,the temperature and damage distribution in the tissue at the time of ultimate damage are discussed from the axial and radial dimensions,*** conclusions and analysis methods proposed in this paper are of great guiding significance for future research in military,medical and many other related fields.

关键词： Laser weapon Non-lethal Limit dose Tissue optics Bioheat transfer Finite element

不同微生物添加剂对桂闽引象草与木薯酒精渣混合微贮品质及有氧稳定性的影响

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饲料研究 2024年第4期47卷 104-109页

作者：罗皎兰罗欢曾俊黄世洋广西大学动物科学技术学院广西南宁530004 广西大学农牧产业发展研究院广西南宁530004

试验旨在探究不同微生物添加剂对桂闽引象草与木薯酒精渣混合微贮品质及有氧稳定性的影响。试验设5个处理,每个处理3个重复,即对照组(CK组,不添加微生物)、Ⅰ组(枯草芽孢杆菌+地衣芽孢杆菌+植物乳杆菌+酵母菌+乳酸菌)、Ⅱ组(乳酸菌+枯... 详细信息

试验旨在探究不同微生物添加剂对桂闽引象草与木薯酒精渣混合微贮品质及有氧稳定性的影响。试验设5个处理,每个处理3个重复,即对照组(CK组,不添加微生物)、Ⅰ组(枯草芽孢杆菌+地衣芽孢杆菌+植物乳杆菌+酵母菌+乳酸菌)、Ⅱ组(乳酸菌+枯草芽孢杆菌+产朊假丝酵母)、Ⅲ组(粪肠球菌+乳酸菌)、Ⅳ组(枯草芽孢杆菌+嗜酸乳杆菌+乳酸菌)。室温避光发酵60 d后取样分析。结果显示,各试验组感官评定结果均优于CK组,其中Ⅰ组最优。与CK组相比,Ⅳ组中性洗涤纤维(NDF)含量显著降低(P<0.05);Ⅰ组和Ⅱ组酸性洗涤纤维(ADF)含量显著降低(P<0.05),Ⅱ组淀粉(Starch)、乙酸、乳酸含量显著降低(P<0.05);Ⅰ组和Ⅲ组水溶性碳水化合物(WSC)含量、30 h中性洗涤纤维消化率显著提高(P<0.05);Ⅲ组的钙(Ca)含量显著升高(P<0.05);Ⅰ组、Ⅱ组和Ⅲ组的乳酸含量显著升高(P<0.05)。Ⅳ组有氧暴露稳定时间最长,为246.67 h,Ⅰ组有氧暴露稳定时间最短,为48 h。通过综合函数分析可得各试验组综合价值均高于CK组,以Ⅰ组最高。研究表明,添加微生物添加剂可提高桂闽引象草与木薯酒精渣混合微贮品质,其中以试验Ⅰ组效果最佳。

关键词：桂闽引象草混合微贮微生物添加剂微贮品质有氧稳定性

维普期刊数据库博看期刊

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新型高丝氨酸脱氢酶的挖掘与改造研究

食品与发酵工业 2024年第12期50卷 9-16页

作者：吴硕黄新燕李梦雅徐宁魏亮刘君中国科学院天津工业生物技术研究所天津300308 河北师范大学生命科学学院河北石家庄050024 南京农业大学生命科学学院江苏南京210000

高丝氨酸脱氢酶(homoserine dehydrogenase,HSD)是L-高丝氨酸和L-苏氨酸等天冬氨酸家族氨基酸生物合成的关键酶,然而由于其活性较低且受到L-苏氨酸等的反馈抑制作用,严重制约了L-高丝氨酸和L-苏氨酸等氨基酸的生物合成水平。该研究通过... 详细信息

高丝氨酸脱氢酶(homoserine dehydrogenase,HSD)是L-高丝氨酸和L-苏氨酸等天冬氨酸家族氨基酸生物合成的关键酶,然而由于其活性较低且受到L-苏氨酸等的反馈抑制作用,严重制约了L-高丝氨酸和L-苏氨酸等氨基酸的生物合成水平。该研究通过数据库检索,挖掘了8个不同来源的高丝氨酸脱氢酶。通过酶活测定分析法发现,来源于二穗短柄草(Brachypodium distachyon)的高丝氨酸脱氢酶BdHSD具有最高的催化活性,达到7.6 U/mg,且不受L-苏氨酸的反馈抑制,其催化最适pH值为10.5,最适催化温度为38℃。随后该研究进一步对BdHSD进行定向进化,提高BdHSD的催化活性。通过多轮筛选获得了3个具有更高催化活性的BdHSD突变体T186A、N283K、A137T/I188V,其中突变体T186A酶活性达到10.3 U/mg,比野生型提高了35.6%。通过L-高丝氨酸发酵分析发现,BdHSD突变体能有效提升L-高丝氨酸的合成水平。综上所述,该研究挖掘和改造了一个具有高效催化特性的高丝氨酸脱氢酶BdHSD,为L-高丝氨酸、L-苏氨酸和L-蛋氨酸等天冬氨酸家族氨基酸的高效生物合成提供了有力的催化元件。

关键词：高丝氨酸脱氢酶酶进化二穗短柄草 L-高丝氨酸抗苏氨酸

Bioaccumulation characterization of uranium by a novel Streptomyces sporoverrucosus dwc-3

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Journal of Environmental Sciences 2016年第3期28卷 162-171页

作者： Xiaolong Li Congcong Ding Jiali Liao Liang Du Qun Sun Jijun yang Yuanyou yang Dong Zhang jun Tang Ning liu Key Laboratory of Radiation Physics and Technology Ministry of EducationInstitute of Nuclear Science and TechnologySichuan University Key Laboratory of Biological Resource and Ecological Environment of the Ministry of Education College of Life SciencesSichuan University Institute of Nuclear Physics and Chemistry CAEP

The biosorption mechanisms of uranium on an aerobic bacterial strain Streptomyces sporoverrucosus dwc-3,isolated from a potential disposal site for（ultra-）low uraniferous radioactive waste in Southwest China,were evaluated by using transmission electron microscopy（TEM）,energy dispersive X-ray（EDX）analysis,Fourier transform infrared spectroscopy（FT-IR）,X-ray photoelectron spectroscopy（XPS）,proton induced X-ray emission（PIXE）and enhanced proton backscattering spectrometry（EPBS）.Approximately60% of total uranium at an initial concentration of 10 mg/L uranium nitrate solution could be absorbed on 100 mg *** dwc-3 with an adsorption capacity of more than3.0 mg/g（wet weight）after 12 hr at room temperature at p H *** dynamic biosorption process of *** dwc-3 for uranyl ions was well described by a pseudo second-order *** dwc-3 could accumulate uranium on cell walls and within the cell,as revealed by SEM and TEM analysis as well as EDX *** and FT-IR analysis further suggested that the absorbed uranium was bound to amino,phosphate and carboxyl groups of the ***,PIXE and EPBS results confirmed that ion exchange also contributed to the adsorption process of uranium.

关键词： Bioaccumulation Uranium Nanoparticle Streptomyces sporoverrucosus dwc-3 Bioremediation

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一种矿卡车用受电弓研制

内燃机与配件 2024年第8期 57-59页

作者：阳凌霄李军中车株洲电力机车有限公司湖南株洲412001

本文介绍了一种为电动矿卡车专门研制的受电弓的技术设计,介绍了其主要技术参数、结构设计、工作原理和液压驱动系统设计。该受电弓基于铁路受电弓的设计原理,考虑电动矿卡车接触网线、自带液压系统的特点,设计采用了一种双受电弓同步... 详细信息

本文介绍了一种为电动矿卡车专门研制的受电弓的技术设计,介绍了其主要技术参数、结构设计、工作原理和液压驱动系统设计。该受电弓基于铁路受电弓的设计原理,考虑电动矿卡车接触网线、自带液压系统的特点,设计采用了一种双受电弓同步升降结构、液压同步驱动系统、多重电气绝缘保护设计的方案,实现了电动矿车车的受流需求,能够有效的满足电动矿用车的应用场景和使用要求,具有较高的指导价值。

关键词：电动矿卡车受电弓技术参数结构设计工作原理液压驱动

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模式识别在贺兰山人面像岩画研究中的应用

甘肃开放大学学报 2024年第1期34卷 26-30页

作者：王阳屈原骏西北大学科学史高等研究院陕西西安710127 西北大学外国语学院陕西西安710127

贺兰山地处古代丝绸之路北道,是东西文明交流的关键节点。利用模式识别等数字技术,以贺兰山的人面像岩画为研究对象,构建贺兰山人面像岩画数据集并训练图像识别模型,成功实现了对人面像岩画的数字化识别,初步展示了模式识别等数字技术... 详细信息

贺兰山地处古代丝绸之路北道,是东西文明交流的关键节点。利用模式识别等数字技术,以贺兰山的人面像岩画为研究对象,构建贺兰山人面像岩画数据集并训练图像识别模型,成功实现了对人面像岩画的数字化识别,初步展示了模式识别等数字技术在岩画研究方面的潜力。研究结果显示多数人面像岩画能够在短时间内被准确识别,可以有效降低个体视觉和经验判断的误差,可以辅助科研人员进行人面像岩画识别,这在岩画研究中具有一定的实用价值,也为深入挖掘岩画文化信息提供了新路径。

关键词：模式识别人面像岩画丝绸之路历史文化

Hierarchical NiCo2O4 microspheres assembled by nanorods with p-type response for detection of triethylamine

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Chinese Chemical Letters 2020年第8期31卷 2077-2082页

作者： Chen yang Yongshan Xu Lingli Zheng Yingqiang Zhao Wei Zheng Xianghong liu jun Zhang College of Physics Center for Marine Observation and CommunicationsQingdao UniversityQingdao 266071China College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJi'nan 250014China

The morphological and structural design provides an efficient protocol to optimize the performance of gas sensing *** this work,a gas sensor with high sensitivity for triethylamine(TEA)detection is developed based on p-type NiCo2 O4 hierarchical *** NiCo2 O4 microspheres,synthesized by a hydrothermal route,have a three-dimensional(3 D)urchin-like structure assembled by nanorod building *** structure-property correlation has been investigated by powder X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscope,scanning electron microscope,N2 adsorption-desorption tests and comprehensive gas sensing *** influence of calcination temperature on the morphological structure and sensing performances has been *** reveal that the material annealed at 300℃has a very large specific surface area of 125.27 m2/g,thereby demonstrating the best TEA sensing properties including high response and low limit of detection(145 ppb),good selectivity and *** further increase of the calcination temperature leads to the collapse of the 3 D hierarchical structure with significantly decreased surface area,which is found to decline the sensing *** work indicates the promise of ternary p-type metal oxide nanostructures for application in highly sensitive gas sensors.

关键词： Microstructures NiCo2O4 Metal oxide p-type response Gas sensor