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Integrating potential distribution of dominant vegetation and land use into ecological restoration in the Yellow River Basin,China

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Journal of Mountain Science 2022年第10期19卷 2886-2904页

作者： JIAN Sheng-qi Zhu Tian-sheng hu cai-hong College of Water Resources and Environment Zhengzhou UniversityZhengzhou 450001China

Due to the influence of human activities such as cultivation and urban construction,the ecosystem of the Yellow River Basin(YRB)is subjected to increased vulnerability and even potential risk of *** restoration has led to an increase in vegetation,but excessive afforestation conversely results in low survival rate of trees,water shortages,and biodiversity *** is of great significance for achieving sustainable development of forests to reasonable revegetation in the *** present,the potential distribution pattern of dominant species and their mixed forms in the basin has not been effectively *** study simulated the potential distribution of dominant vegetation in the YRB based on Maximum Entropy(Max Ent)and Genetic Algorithm for Rule-Set Prediction(GARP)and explored the impact of human interference on it by employing land use as the environmental filter to distinguish the regions of human *** further predicted the potential distribution of typically mixed forests and discussed their human *** main results are as follows:(1)Except for Caragana korshinskii,all models had good above performance(0.7human activities caused great damage to the core growth regions of these vegetation.(3)Mean temperature of c

关键词： Yellow River Potential distribution Land use Mixed forests Vegetation restoration

Cyano and Isocyano-substituted Tetraphenylethylene with AIE Behavior and Mechanoresponsive Behavior

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Chinese Journal of Structural Chemistry 2022年第4期41卷 75-82页

作者： Qing Liu Shusheng Yue Zhangqiang Yan Yongfa Xie hu cai School of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China

Dual-functional materials with AIE behavior and mechanoresponsive behavior have attracted considerable attention due to their promising applications in mechano-sensors,optical storage,solid-state optoelectric devices and bioimage *** bearing tetraphenylethylene(TPE)core become elementary building blocks in many fluorescent functional *** this article,cyanoand isocyano-electronic withdrawing groups are incorporated with TPE skeleton to form tetracyanophenylethylene(TPE-CN)and tetraisocyanophenylethylene(TPE-NC).Their structures are confirmed by NMR,Mass Spectra and single crystal X-ray *** two isomers reflect aggregation-induced emission(AIE)property in solution state and mechanochromic behavior in solid ***,their luminescent intensities,quantum yields and fluorescent lifetime in solid state have an obvious increase upon *** theoretical calculation of these two compounds clarify their difference in optical *** mechanochromic mechanism is also intensively explained by powder X-ray measurements.

关键词： cyano-group isocyano-group tetraphenylethlene(TPE) aggregation induced emission(AIE) mechanochromic

Shape optimization of axisymmetric solids with the finite cell method using a fixed grid

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Acta Mechanica Sinica 2016年第3期32卷 510-524页

作者： Liang Meng Wei-Hong Zhang Ji-Hong Zhu Zhao Xu Shou-hu cai Engineering Simulation and Aerospace Computing (ESAC) Northwestern Polytechnical University

In this work, a design procedure extending the B-spline based finite cell method into shape optimization is developed for axisymmetric solids involving the centrifugal force effect. We first replace the traditional conforming mesh in the finite element method with structured cells that are fixed during the whole design process with a view to avoid the sophisticated re-meshing and eventual mesh ***, B-spline shape functions are further implemented to yield a high-order continuity field along the cell boundary in stress analysis. By means of the implicit description of the shape boundary, stress sensitivity is analytically derived with respect to shape design variables. Finally, we illustrate the efficiency and accuracy of the proposed protocol by several numerical test cases as well as a whole design procedure carried out on an aeronautic turbine disk.

关键词： Finite cell method(FCM) Shape optimization B-spline Sensitivity analysis Axisymmetric solids

Synthesis and Characterization of Polyamide-Containing 2, 6-(Substituded) pyridine Derivatives

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 682-686页

作者： XU Kuoxi hu Peizhi cai Lihua Colliege of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 Hubei China

A new series of acyelic aromatic polyamide pyridine derivatives a-h and a new macrocyclic polyamide containing pyridine ring i were synthesized by the reaction of N^2, N^6-his（2-aminoethyl） pyridine-2, 6-dicarboxamide or N^2 , N^6-bis （3-aminopropyl） pyridine-2,6-dicarboxamide with various acyl chloride. The compounds were characterized by MS, ^1H NMR, IR and elemental analysis. The single-crystal structure of g confirmed that the crystal is of triclinic, space group P-1 with Mr = 487.55, α=9.3031（19）, b=12.167（2） , c=126.50（3） nm, α=108.91（3）°, β= 97. 57（3）°, γ=102.07（3）°, Ⅴ= 1 293.5 nm, Z=2, Dc=1. 252 kg/m^3, μ=0. 086 mm^-1, F（000）=516, X-ray analysis reveals that there exist hydrogen bonding and network structure in the crystal.

关键词： polyamide pyridine derivative synthesis crystal structure

Synthesis Hexadecyl 3-{4-[2-Hydroxy-3(isopropylamino)propoxy] phenyl}propionate as Potential Ligand for Liposome Targeting to Ischemic Myocardium

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Chinese Chemical Letters 2005年第8期16卷 1004-1006页

作者： Yan Li HAO Ying Jie DENG Yan CHEN You cai hu Department of Pharmaceutical Sciences Shenyang Pharmaceutical UniversityShenyang 110016 Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050

Novel hexadecyl 3-{4-[2-hydroxy-3(isopropylamino)propoxy]phenyl}propionate(HPP)was synthesized and its effect on delivery of liposomes into cultured cardiomyocytes was *** structure of HPP was characterized by IH NMR,1R and *** amount of cardiomyocytes uptake of HPP-liposome was 3.9-fold higher than plain-liposome,and the increase was 6.2-fold when hypoxia *** indicated that HPP was a potential ligand for liposome targeting to ischemic myocardium.

关键词： Hexadecyl 3-{4-[2-hydroxy-3(isopropylamino)propoxy]phenyl}propionate liposome,targeting ischemic myocardium.

Dichloromethane as a methylene synthon for regioselective linkage of diverse carboxylic acids:Direct access to methylene diesters under metal-free conditions

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Chinese Chemical Letters 2019年第6期30卷 1173-1177页

作者： Shuiliang Wang Zhengjiang Fu Zhicong huang Yongqing Jiang Shengmei Guo hu cai College of Chemistry Nanchang University Nanchang 330031 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter CAS Fuzhou 350002 China

A metal-free cross coupling between common CH2Cl2 and carboxylic acids has been achieved with K2CO3 as the sole additive. This simple protocol is a convenient and cost-effective route to synthesize methylene diesters from a wide scope of carboxylic acids substrates with good functional group tolerance. Several gram-scale reactions have been performed to evaluate the effectiveness and practicality of this protocol.

关键词： Carboxylic acids Dichloromethane Methylene synthon Methylene diesters Metal-free conditions

A New Triterpene from Cynanchum forrestii

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Chinese Chemical Letters 2006年第12期17卷 1569-1572页

作者： Yue LIU Jing QU Shi Shan YU Jing LIU You cai hu Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education ＆ Institute of Materia Medica Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100050

A new triterpene, named cynanotriterpene A, with a ring-A-fission （3, 4-seco） and 13, 27-cyclours-3-oic acid methyl ester skeleton was isolated from the roots of Cynanchum forrestii Schlechter. The structure of the ... 详细信息

关键词： Cynanchumforrestii triterpene X-ray diffraction.

The expression of Lin28B was co-regulated by H3K4me2 and Wnt5a/β-catenin/TCF7L2

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Journal of Integrative Agriculture 2020年第12期19卷 3054-3064页

作者： ZHANG Ya-ni hu cai WANG Ying-jie ZUO Qi-sheng LI Bi-chun Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province College of Animal Science and TechnologyYangzhou UniversityYangzhou 225009P.R.China Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education Yangzhou UniversityYangzhou 225009P.R.China

Lin28A and Lin28B are homologous RNA-binding proteins that participate in the development of primordial germ cells. The mechanisms underlying expression and regulation of Lin28A have been well documented, but such information for Lin28B is limited. In this study, a fragment of the Lin28B promoter was cloned, the pEGFP-pLin28B vector was constructed. DF-1 chicken fibroblasts were transfected and the expression of green fluorescent protein (GFP) was measured. Furtherly, Lin28B promoter of different lengths fragments was cloned using the chromosome-walking method and the fragments were ligated into the PGL3-Basic vector, and transfected into DF-1 cells. Results of dual-luciferase reporter assay showed that the core of the Lin28B promoter was included in the sequence from –1 431 to –1 034 bp. The binding sites of the transcription factor TCF7L2 was showed within this sequence by bioinformatics analysis. The promoter activity of Lin28B was downregulated (P<0.05) when the TCF7L2 binding site was mutated. Further experiments suggested that Lin28B promoter activity responded to the activation or inhibition of Wnt signaling. Results of chromatin immunoprecipitation and quantitative PCR showed that β-catenin-TCF7L2 may be enriched in the Lin28B promoter core area. In vivo and in vitro activation or inhibition of Wnt signaling significantly up- or down-regulated (P<0.05) Lin28B expression. H3K4me2 enriched in the promoter of Lin28B, which affected the regulation of Wnt signaling to Lin28B. In conclusion, our results showed that H3K4me2 and Wnt5a/β-catenin/TCF7L2 were the positive regulators of Lin28B expression. Findings of this study may lay a theoretical foundation for illuminating the mechanism underlying Lin28B expression.

关键词： primordial germ cells Lin28B promoter H3K4me2 Wnt5a/β-catenin/TCF7L2

Current Soil Nutrient Status of Intensively Managed Greenhouses

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Pedosphere 2012年第6期22卷 825-833页

作者： hu Yun-cai SONG Zhi-Wen LU Wen-Long C. POSCHENRIEDER U. SCHMIDHALTER Chair of Plant Nutrition Technische Universitat Miinchen D-85350 Freising (Germany) Institute of Information Tianjin Academy of Agricultural Sciences Tianjin (China)

Nine districts covering the main greenhouse vegetable areas in Tianjin Municipality of the North China Plain were selected for the soil investigation in 2010 to survey the current soil nutrient status (soil available N, P and K), acidification and salinization due to excessive input of fertilizers in greenhouses in Tianjin. The study showed that, in particular, soil available P content increased with the age of greenhouses. In contrast, our results did not reveal higher K accumulation and lowered pH in the greenhouse soils compared with cultivation in open fields. Over-fertilization, causing high NO 3 accumulation, most likely resulted in salinity problems in the greenhouses. Ninety percent of the investigated greenhouse soils had electrical conductivity values of saturated paste extracts of 2-10 d S m-1 , which might affect the yields of vegetable crops like green bean, pepper, cabbage, carrot, eggplant, lettuce, spinach, celery, cucumber and tomato. The findings of our survey of the current fertility and salinity problems in greenhouse soils suggest that there is an urgent need to improve the farmers' practices and strategies in fertilization management in greenhouses of China. Because education and the agricultural technical extension services may play a more important role in avoiding overuse of fertilizers, we suggest that current nutrient management practices should be improved in the near future through training of local farmers in farmers' schools and through strengthening the agricultural extension services with practical techniques.

关键词： electrical conductivity greenhouse vegetables over-fertilization soil pH soil survey