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Geochemistry, zircon U–Pb geochronology, and Hf isotopes of S-type granite in the Baoshan block, constraints on the age and evolution of the Proto-Tethys
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作者 jianjun zhang Chuanlong Mou +3 位作者 Chendong Liu Yong zhang Ting Chen Hualiang Li 《Acta Geochimica》 EI CAS CSCD 2024年第1期40-58,共19页
Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkali... Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkaline, strongly peraluminous rocks with A/CNK values of 1.37–1.46, are enriched in SiO2, K2O, and Rb, and are depleted in Nb, P, Ti, Eu, and heavy rare earth elements,which indicates the crystallization fractionation of the granitic magma. Zircon U–Pb dating indicates that they formed in ca. 480 Ma. The Nansa granites have εHf(t) values ranging from-16.04 to 4.36 with corresponding TC DMages of 2.10–0.81 Ga, which suggests the magmas derived from the partial melting of ancient metasedimentary with minor involvement of mantle-derived components. A synthesis of data for the Early Paleozoic igneous rocks in the Baoshan block and adjacent(Tengchong,Qiangtang, Sibumasu, Himalaya, etc.) blocks indicates that these blocks were all aligned along the proto-Tethyan margin of East Gondwana in the Early Paleozoic. The Early Paleozoic S-type granites from Nansa were generated in a high-temperature and low-pressure(HTLP) extensional tectonic setting, which resulted from Andean-type orogeny instead of the final assembly of Gondwana or crustal extension in a non-arc environment. In certain places, an expanding environment may exist in opposition to the tectonic backdrop of the lithosphere’s thickening and shortening, leading the crust to melt and decompress,mantle-derived materials to mix, and a small quantity of peraluminous granite to emerge. 展开更多
关键词 Baoshan block Early Paleozoic GRANITE GEOCHEMISTRY ZIRCON GEOCHRONOLOGY Hf isotope
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Train post‑derailment behaviours and containment methods:a review
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作者 Zhao Tang Yuwei Hu +3 位作者 Shuangbu Wang Liang Ling jianjun zhang Kaiyun Wang 《Railway Engineering Science》 EI 2024年第1期59-80,共22页
Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment ... Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment behaviours and containment methods play a critical role in preventing derailment escalation and providing passive safety protection and accident prevention in the event of a derailment.However,despite the increasing attention on this field from academia and industry in recent years,there is a lack of systematic exploration and summarization of emerging applications and containment methods in train post-derailment research.For this reason,this paper presents a comprehensive review of existing studies on train post-derailment behaviours,encompassing various topics such as post-derailment contact-impact models,dynamic modelling and simulation techniques,and the primary factors influencing post-derailment behaviours.Significantly,this review introduces and elucidates substitute guidance mechanisms(SGMs),which serve as railway-specific passive safety protection and accident prevention measures.The various types of SGMs are depicted,and their ongoing developments and applications are explored in depth.The review additionally points out several unresolved challenges including the adverse effects of SGMs,and proposes future research directions to advance the theoretical understanding and practical application of train post-derailment behaviours and containment methods.This review seeks to be a valuable reference for railway industry professionals in preventing catastrophic derailment consequences through post-derailment containment methods. 展开更多
关键词 Railway passive safety Railway accident prevention Post-derailment behaviours Substitute guidance mechanisms(SGMs) Contact-impact model
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Regional Brand and High-quality Development of Fruits in Ethnic Areas of the Yangtze River Economic Belt under the Greater Food Approach
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作者 Li GAO jianjun zhang +2 位作者 Yuanpeng SUN Zhiyang LIU Zhiguo SUN 《Asian Agricultural Research》 2024年第3期1-7,共7页
Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.T... Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.This paper introduces the characteristics of fruit industry in 16 autonomous prefectures and 47 autonomous counties under the jurisdiction of the Yangtze River Economic Belt.It studies the intellectual property resources of brand marks from the aspects of geographical indications,collective trademarks,certification trademarks,well-known trademarks in China and national design patents,and analyzes the main problems of brand and high-quality development of fruit industry in these ethnic autonomous areas.Finally,it puts forward some strategies,such as improving the protection of intellectual property rights of geographical indications,using intellectual property rights of brand signs,building modern seed industry upgrading project,drawing lessons from the experience of thousand villages demonstration project,ensuring that large-scale poverty does not occur,and building a diversified food supply system. 展开更多
关键词 GREATER FOOD APPROACH Fruit industry Regional brand The Yangtze River Economic Belt ETHNIC areas
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Promoting High-quality Development of Grain and Oil in Ethnic Areas of the Yangtze River Economic Belt from the Perspective of Agricultural Power
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作者 Li GAO jianjun zhang +2 位作者 Yuanpeng SUN Zhiyang LIU Zhiguo SUN 《Asian Agricultural Research》 2024年第2期1-7,11,共8页
Accelerating the construction of agricultural power,further promoting the high-quality development of the Yangtze River Economic Belt,and better supporting and serving Chinese-style modernization are the key issues at... Accelerating the construction of agricultural power,further promoting the high-quality development of the Yangtze River Economic Belt,and better supporting and serving Chinese-style modernization are the key issues at present.This paper first introduces the Yangtze River Economic Belt and its ethnic areas,and studies the characteristics of the grain and oil industry in the ethnic autonomous areas of the economic belt,as well as the current situation of various types of intellectual property resources,such as industrial cultural heritage,scientific and tech-nological innovation,and brand marking intellectual property.Besides,it analyzes the main problems in the high-quality development of grain and oil in the Yangtze River Economic Belt ethnic areas.Finally,it comes up with recommendations,including protecting the intellectual prop-erty rights of cultural heritage in the field of grain and oil,leading the inheritance and development of excellent traditional Chinese culture,use scientific and technological innovation intellectual property rights to promote the innovation-driven development strategy of the grain and oil in-dustry,and providing counterpart assistance to ethnic autonomous areas in the Yangtze River Economic Belt to further promote the high-quality development of the Yangtze River Economic Belt. 展开更多
关键词 The Yangtze River Economic Belt Ethnic areas Grain and oil Intellectual property Agricultural power
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MOF/CdS梯型光催化剂同时进行苯甲醇氧化和析氢反应及其机理研究
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作者 刘博文 蔡家杰 +3 位作者 张建军 谭海燕 程蓓 许景三 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第8期204-215,共12页
太阳能驱动的光催化水分解制氢是一种清洁、可持续的技术,可以减少碳排放.一般来说,光催化全解水的析氧半反应过程需要消耗四个空穴,且迟缓的反应动力学会抑制整体反应,因此光催化全解水极具挑战性.在光催化制氢中通常利用空穴牺牲剂来... 太阳能驱动的光催化水分解制氢是一种清洁、可持续的技术,可以减少碳排放.一般来说,光催化全解水的析氧半反应过程需要消耗四个空穴,且迟缓的反应动力学会抑制整体反应,因此光催化全解水极具挑战性.在光催化制氢中通常利用空穴牺牲剂来提升产氢半反应的效率.然而,这些过程会产生无用的氧化产物,造成光生空穴氧化能力的浪费,且增加了系统成本.因此,构建一个由光催化产氢和选择性有机合成相结合的双功能氧化还原体系,可同时利用光生电子和空穴,并且产物中氢气和高附加值的有机产品容易分离,因此具有较高的可持续经济效应.利用梯型异质结将两种带隙适合且能带结构匹配的光催化剂复合在一起,可以最大程度地利用两种光催化剂的氧化还原能力,为解决上述问题提供了一条理想途径.本文采用化学浴法将CdS纳米颗粒原位生长在锆基金属有机框架UiO-66-NH_(2)(U6N)上.在光照条件下,梯型异质结催化苯甲醇选择性氧化生成苯甲醛和氢气的性能大幅度提升,UC0.75(U6N/CdS理论质量比为0.75)复合物光照3 h产氢速率为630μmol·g^(-1)h^(-1),同时苯甲醇氧化为苯甲醛的选择性达到99%.原位辐照X射线光电子能谱结果表明,UC0.75梯型异质结界面的电子转移路径,在暗态下电子由CdS转移到U6N,在光照下电子由U6N转移到CdS.利用飞秒瞬态吸收(fs-TA)光谱进一步研究了异质结的载流子迁移的动力学信息,结果表明,复合样品中基态漂白信号衰减时间减少,梯型异质结界面处电子转移效率较高.此外,通过原位漫反射红外傅里叶变换光谱、电子顺磁共振和同位素实验揭示了苯甲醇的氧化机理,光照下,位于U6N的光生空穴与苯甲醇相互作用,先氧化苯甲醇上的α-C产生·CH(OH)Ph,然后进一步氧化产生苯甲醛,同时,CdS上的光生电子与水中产生的H+结合产生氢气.综上,本文通过飞秒瞬态吸收光谱(fs-TAS)光谱来阐述梯型异质结的电子转移机制,并为金属有机框架/无机物复合光催化剂的设计提供了借鉴. 展开更多
关键词 梯型异质结 光催化产氢 选择性有机氧化 超快光谱
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Inheritance,Innovation and High-quality Development of Herbaceous Edible Oils in Hubei Province under the Strategy of Strengthening the Country with Intellectual Property 被引量:1
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作者 Li GAO Yuanpeng SUN +2 位作者 Jin ZENG jianjun zhang Zhiguo SUN 《Asian Agricultural Research》 2023年第12期5-15,共11页
Only by improving the production capacity of domestic herbal edible oil can China ensure the safety of the supply chain of the important industrial chain of vegetable edible oil in China and practice the big food conc... Only by improving the production capacity of domestic herbal edible oil can China ensure the safety of the supply chain of the important industrial chain of vegetable edible oil in China and practice the big food concept.In addition to rice,maize,and soybean for using as grain and oil,there are eight kinds of herbaceous edible oil crops in Hubei Province,including rape,peanut,sesame,sunflower,perilla(perilla seed),cotton,linen and tiger nut(Cyperus esculentus).This paper studies the main industries of herbaceous edible oil crops and their intellectual property resources in Hubei Province,and analyzes the main problems of its inheritance,innovation and high-quality development under the strategy of strengthening the country with intellectual property.Finally,it proposes the countermeasures of carrying forward and inheriting traditional knowledge and traditional culture,maintaining the biodiversity of crops,strengthening the creation of new plant varieties and breeding patents,and opening up the whole chain of intellectual property rights. 展开更多
关键词 HERBACEOUS EDIBLE OIL crops Vegetable EDIBLE OIL Big food concept INTELLECTUAL property right Hubei Province
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Intellectual Property Protection,Inheritance,Innovation and Development of Woody Edible Oilseeds in Hubei Province 被引量:1
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作者 Li GAO Yuanpeng SUN +2 位作者 jianjun zhang Jin ZENG Zhiguo SUN 《Asian Agricultural Research》 2023年第11期6-14,共9页
Only by developing woody edible oilseeds industry can we ensure the safety of the important industrial chain and supply chain of vegetable edible oil in China.There are 13 kinds of woody edible oil plants in Hubei,inc... Only by developing woody edible oilseeds industry can we ensure the safety of the important industrial chain and supply chain of vegetable edible oil in China.There are 13 kinds of woody edible oil plants in Hubei,including Camellia oleifera Abel(oil tea),Juglans regia L.(walnut),Olea europaea L.(olive)and Paeonia suffruticosa(oil peony).This paper studies the main industries of woody edible oilseeds in Hubei Province and their intellectual property resources,and analyzes the main problems in their intellectual property protection,inheritance,innovation and development.Finally,it proposes some strategies,including carrying forward the traditional knowledge related to woody edible oilseeds,innovating the"agricultural chip",creating key counties of national woody edible oil seeds,and developing industrial clusters with national advantages and characteristics. 展开更多
关键词 Woody edible oilseeds Vegetable edible oil Grain and oil Safety Big food concept Intellectual property rights Hubei Province
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Configuration Design and Kinematic Performance Analysis of a Novel 4-DOF Parallel Ankle Rehabilitation Mechanism with Two Virtual Motion Centers
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作者 Jingke Song Jun Wei +3 位作者 Bin Yu Chenglei Liu Cunjin Ai jianjun zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期87-104,共18页
Aiming at the problem that the existing ankle rehabilitation robot is difficult to fully fit the complex motion of human ankle joint and has poor human-machine motion compatibility,an equivalent series mechanism model... Aiming at the problem that the existing ankle rehabilitation robot is difficult to fully fit the complex motion of human ankle joint and has poor human-machine motion compatibility,an equivalent series mechanism model that is highly matched with the actual bone structure of the human ankle joint is proposed and mapped into a parallel rehabilita-tion mechanism.The parallel rehabilitation mechanism has two virtual motion centers(VMCs),which can simulate the complex motion of the ankle joint,adapt to the individual differences of various patients,and can meet the reha-bilitation needs of both left and right feet of patients.Firstly,based on the motion properties and physiological structure of the human ankle joint,the mapping relationship between the rehabilitation mechanism and ankle joint is determined,and the series equivalent model of the ankle joint is established.According to the kinematic and con-straint properties of the ankle equivalent model,the configuration design of the parallel ankle rehabilitation robot is carried out.Secondly,according to the intersecting motion planes theory,the full-cycle mobility of the mechanism is proved,and the continuous axis of the mechanism is judged based on the constraint power and its derivative.Then,the kinematics of the parallel ankle rehabilitation robot is analyzed.Finally,based on the OpenSim biomechanical soft-ware,a human-machine coupling rehabilitation simulation model is established to evaluate the rehabilitation effect,which lays the foundation for the formulation of a rehabilitation strategy for the later prototype. 展开更多
关键词 Ankle rehabilitation robot Double-VMCs mechanism Kinematic performance Human-machine rehabilitation simulation
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Trade-offs between ion-conducting and mechanical properties: The case of polyacrylate electrolytes
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作者 Guoli Lu Yaojian zhang +7 位作者 jianjun zhang Xiaofan Du Zhaolin Lv Junzhe Du Zhiming Zhao Yue Tang Jingwen Zhao Guanglei Cui 《Carbon Energy》 SCIE CSCD 2023年第2期24-60,共37页
Polymer electrolytes(PEs)have been long recognized as the key materials to enable energy-dense batteries and render flexible energy devices practically viable,owing to their chemical and mechanical reliability.However... Polymer electrolytes(PEs)have been long recognized as the key materials to enable energy-dense batteries and render flexible energy devices practically viable,owing to their chemical and mechanical reliability.However,much of their promise is yet to be realized.The roomtemperature ion conductivity of existing PEs still falls short of the implementation criterion of 10^(-4) S cm^(-1) on the promise of acceptable mechanical properties,thereby precluding their practical application.The twin but inversely related duties of polymers,that is,functioning as both an ion-conducting medium and a structural backbone,underlie this issue but are less elucidated systematically.The polyacrylate(PA)family is among promising polymer matrices on account of ester polarity,electrode compatibility,chemical tunability,and mechanical durability.The extensive applicability of PA in plasticized gels,dry solids,and emerging composites makes PA-based PEs representative to illustrate the trade-off between ion conduction and mechanical strength.We herein seek to outline the stated long-standing conflict exemplified by PA-based PEs,focusing on crucial strategies toward balancing and reconciling the two mutually exclusive properties,with the intention of offering designing guidelines for next-generation PEs. 展开更多
关键词 ionic conductivity lithium batteries mechanical properties POLYACRYLATE polymer electrolytes trade-offs
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Application of Time Serial Model in Water Quality Predicting
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作者 Jiang Wu jianjun zhang +7 位作者 Wenwu Tan Hao Lan Sirao zhang Ke Xiao Li Wang Haijun Lin Guang Sun Peng Guo 《Computers, Materials & Continua》 SCIE EI 2023年第1期67-82,共16页
Water resources are an indispensable and valuable resource for human survival and development.Water quality predicting plays an important role in the protection and development of water resources.It is difficult to pr... Water resources are an indispensable and valuable resource for human survival and development.Water quality predicting plays an important role in the protection and development of water resources.It is difficult to predictwater quality due to its random and trend changes.Therefore,amethod of predicting water quality which combines Auto Regressive Integrated Moving Average(ARIMA)and clusteringmodelwas proposed in this paper.By taking thewater qualitymonitoring data of a certain river basin as a sample,thewater quality Total Phosphorus(TP)index was selected as the prediction object.Firstly,the sample data was cleaned,stationary analyzed,and white noise analyzed.Secondly,the appropriate parameters were selected according to the Bayesian Information Criterion(BIC)principle,and the trend component characteristics were obtained by using ARIMA to conduct water quality predicting.Thirdly,the relationship between the precipitation and the TP index in themonitoring water field was analyzed by the K-means clusteringmethod,and the random incremental characteristics of precipitation on water quality changes were calculated.Finally,by combining with the trend component characteristics and the random incremental characteristics,the water quality prediction results were calculated.Compared with the ARIMA water quality prediction method,experiments showed that the proposed method has higher accuracy,and its Mean Absolute Error(MAE),Mean Square Error(MSE),and Mean Absolute Percentage Error(MAPE)were respectively reduced by 44.6%,56.8%,and 45.8%. 展开更多
关键词 ARIMA CLUSTER correlation analysis water quality predicting
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Correlation Analysis of Turbidity and Total Phosphorus in Water Quality Monitoring Data
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作者 Wenwu Tan jianjun zhang +7 位作者 Xing Liu Jiang Wu Yifu Sheng Ke Xiao Li Wang Haijun Lin Guang Sun Peng Guo 《Journal on Big Data》 2023年第1期85-97,共13页
At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the p... At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the prediction of total phosphorus in water quality has good research significance.This paper selects the total phosphorus and turbidity data for analysis by crawling the data of the water quality monitoring platform.By constructing the attribute object mapping relationship,the correlation between the two indicators was analyzed and used to predict the future data.Firstly,the monthly mean and daily mean concentrations of total phosphorus and turbidity outliers were calculated after cleaning,and the correlation between them was analyzed.Secondly,the correlation coefficients of different times and frequencies were used to predict the values for the next five days,and the data trend was predicted by python visualization.Finally,the real value was compared with the predicted value data,and the results showed that the correlation between total phosphorus and turbidity was useful in predicting the water quality. 展开更多
关键词 Correlation analysis CLUSTER water quality predict water quality monitoring data
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The Role and Mechanism of LncRNA-p21 in Regulating Gastric Cancer Metastasis by Mediating Wnt/β-Catenin Signaling Pathway
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作者 Peng Liu Haizhe Chang +3 位作者 Xinyu Peng Xiu zhang jianjun zhang Jiusong Luan 《Journal of Clinical and Nursing Research》 2023年第3期143-148,共6页
Objective:To study the mechanism of lncRNA p21 inhibiting the growth and metastasis of human gastric cancer SGC7901/GES-1 cells by mediating the Wnt/β-catenin signaling pathway.Methods:Lentiviral overexpression of ln... Objective:To study the mechanism of lncRNA p21 inhibiting the growth and metastasis of human gastric cancer SGC7901/GES-1 cells by mediating the Wnt/β-catenin signaling pathway.Methods:Lentiviral overexpression of lncRNA-p21 in human gastric cancer SGC7901/GES-1 cell transfections was observed and analyzed for in vitro migration,invasion,cell morphology and proliferation.Besides.Wnt/β-catenin signaling pathway was tested for direct involvement in lncRNA-p21-mediated inhibition of gastric cancer cell growth and proliferation.Wnt/β-catenin signaling pathway was validated using Li-C1.Results:Gastric cancer SGC7901/GES-1 cells in the overexpression of lncRNA-p21 showed changes in stellate morphology,low invasion,or spindle-shaped morphology.LncRNA-p21 inhibited the growth and proliferation of gastric cancer SGC7901/GES-1 cells both in vivo and in vitro,and Wnt/β-catenin signaling pathway mediated the proliferation,invasion,and migration of lncRNA-p21 on gastric cancer SGC7901/GES-1 cells.Conclusion:LncRNA-p21 can inhibit the growth and metastasis of gastric cancer SGC7901/GES-1 cells in vitro and in vivo,and the inhibition of lncRNA p21 is mainly mediated by inhibiting the Wnt/β-catenin signaling pathway. 展开更多
关键词 LncRNA-p21 Wnt/beta-catenin signaling pathway Gastric cancer
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Role of CST1 in Promoting Gastric Cancer Metastasis and Analysis of Its Mechanism
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作者 Jianfei Wu Xinmei Hu +3 位作者 Xinyu Peng Xiu zhang jianjun zhang Peng Liu 《Proceedings of Anticancer Research》 2023年第3期58-63,共6页
Objective:To elucidate the role and mechanism of cysteine protease inhibitor SN(CST1)in promoting the metastasis of gastric cancer.Methods:(1)Firstly,6 pairs of cancer and paracancer tissue samples from gastric cancer... Objective:To elucidate the role and mechanism of cysteine protease inhibitor SN(CST1)in promoting the metastasis of gastric cancer.Methods:(1)Firstly,6 pairs of cancer and paracancer tissue samples from gastric cancer patients without distant metastasis and 5 pairs of cancer and paracancer tissue samples from gastric cancer patients with peritoneal metastasis were collected for transcriptome sequencing.Statistical analysis was performed on the sequencing results to identify significantly upregulated differential genes.(2)Another 75 pairs of cancer and paracancer tissue samples were collected from gastric cancer patients,and the protein and total RNA of gastric cancer tissue samples were extracted.Western blot and quantitative reverse transcription polymerase chain reaction(qRT-PCR)were used to detect the expression of CST1 protein and messenger RNA(mRNA)in gastric cancer and adjacent tissues.(3)The total protein and total RNA of AGS,BGC823,HGC-27,MGC803,MKN45,SGC7901,and SNU-1 gastric cancer cells and normal gastric mucosal epithelial cells GES-1 were extracted.Western blot and qRT-PCR were used to detect CST1 protein and mRNA expression.Results:(1)The significantly upregulated differential gene CST1 was screened,and the expression of CST1 in gastric cancer tissues was significantly higher than that in adjacent tissues.(2)Compared with normal gastric mucosal epithelial cells GES-1,the expression of CST1 in gastric cancer cell lines was upregulated,and the expression of CST1 in HGC-27 and SNU-1 was relatively low,while the expression of CST1 in AGS and MKN45 was relatively high.At the same time,a stable cell line of HGC-27 overexpressing CST1 and MKN45 knocking down CST1 was successfully constructed.(3)Overexpression or knockdown of CST1 did not significantly change the proliferation ability of gastric cancer cells,but can promote the migration and invasion of gastric cancer cells.(4)CST1 may promote the metastasis of gastric cancer cells by activating the epithelial-mesenchymal transition(EMT)signaling pathway.Conclusion:CST1 gene promotes the migration of gastric cancer cells,and we found through animal experiments that CST1 can affect the metastasis and invasion function of gastric cancer and is negatively correlated with the level of E-cadherin. 展开更多
关键词 CST1 Gastric cancer MECHANISM
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基于超声波联用技术的中药材党参绿色养护的可行性
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作者 李芳蓉 刘凤霞 +2 位作者 牛娟 张建军 赵云峰 《中兽医学杂志》 2020年第9期85-90,共6页
绿色养护中药材党参的迫切而必要,超声清洗和果蔬、食品的绿色防腐保鲜技术和方法,应用于党参药材贮藏养护科学、可行。超声波联用技术养护党参后评价养护效果的待检药效成分和质量标准成分及其测定方法,分别选定为HPLC法测定党参炔苷... 绿色养护中药材党参的迫切而必要,超声清洗和果蔬、食品的绿色防腐保鲜技术和方法,应用于党参药材贮藏养护科学、可行。超声波联用技术养护党参后评价养护效果的待检药效成分和质量标准成分及其测定方法,分别选定为HPLC法测定党参炔苷、苍术内酯Ⅲ,UV-Vis法测定党参多糖,选定的测定成分代表性强,测定方法经典科学,简捷高效,重现性好,稳定性高,应用广泛。将超声波及其联用技术应用于党参药材绿色养护中,研究和应用前景光明广阔。 展开更多
关键词 超声波联用技术 党参 绿色养护 可行性
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CdS/Pt异质结光催化剂光解水的电子转移动力学 被引量:1
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作者 张建军 杨高元 +4 位作者 何博文 程蓓 李佑稷 梁桂杰 王临曦 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2530-2538,共9页
为缓解能源危机和环境污染,开发和利用高热值和零污染的氢气至关重要.近年来,半导体光催化分解水制氢技术在科研领域受到广泛关注.CdS是一种常用的光解水催化剂,但单一CdS光催化剂的光生电子和空穴易复合,并且该复合过程发生在皮秒到纳... 为缓解能源危机和环境污染,开发和利用高热值和零污染的氢气至关重要.近年来,半导体光催化分解水制氢技术在科研领域受到广泛关注.CdS是一种常用的光解水催化剂,但单一CdS光催化剂的光生电子和空穴易复合,并且该复合过程发生在皮秒到纳秒级.大部分光生电子无法迁移到光催化剂表面参与析氢反应,导致其产氢效率低.贵金属助催化剂在提高CdS光催化分解水性能方面展现出巨大的潜力,然而贵金属修饰的CdS在实际析氢过程中的电子动力学机制尚不清楚.此外,光生载流子转移过程一般发生在飞秒和皮秒尺度,很难通过普通的光学表征来探测这一动力学过程.因此,深入研究光生载流子的转移动力学过程对揭示CdS基复合光催化材料析氢性能增强的动力学机制具有重要意义.本文利用Pt纳米颗粒修饰的CdS纳米棒来研究CdS/Pt异质结中的超快电子转移动力学过程.首先通过水热法合成CdS纳米棒,再利用原位光还原的方法将Pt纳米颗粒沉积到CdS纳米棒表面.在合成CdS/Pt过程中,PtCl_(6)^(2–)通过库仑作用吸附到CdS纳米棒表面带正电的缺陷位点,并利用CdS纳米棒产生的光生电子将PtCl_(6)^(2–)还原成Pt纳米颗粒,从而得到CdS/Pt肖特基异质结光催化剂.借助飞秒瞬态吸收光谱技术探究CdS和CdS/Pt在乙腈和纯水中的电子转移动力学过程.对于单一组分的CdS,主要有三种激子猝灭途径,包括电子的浅缺陷态俘获(~6.8 ps)、电子和被俘获的空穴的复合(~58.2 ps),以及导带底电子和价带顶空穴的荧光辐射复合(~2611.9 ps).原位沉积的Pt纳米颗粒可钝化CdS表面的缺陷,并且光生电子的浅缺陷态俘获过程得到显著的抑制.此外,Pt助催化剂的引入在CdS/Pt界面构建了超快电子传输通道.对于分散在乙腈中的CdS/Pt,界面电子转移的时间和速率为~5.5 ps和~3.5×10^(10) s^(−1).在模拟光解水过程中,CdS/Pt界面的电子转移时间减少到~5.1 ps,并且其电子转移速率增大到~4.9×10^(10) s^(−1),证实了Pt纳米颗粒是光催化产氢反应的活性位点.综上,本文从电子动力学角度揭示了Pt助催化剂提高CdS光解水性能的机理,为设计新型高效的CdS基光催化剂提供了指导和新思路. 展开更多
关键词 飞秒瞬态吸收光谱 光催化分解水 CDS 电子转移动力学 俘获态
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原位制备氧化钛/氮掺杂石墨烯空心球光催化剂及其光催化CO_(2)还原性能研究 被引量:1
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作者 王立博 朱必成 +3 位作者 程蓓 张建军 张留洋 余家国 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第10期1648-1658,共11页
利用光催化技术将二氧化碳转化为化学燃料是缓解温室效应以及能源危机的理想途径之一.因此,开发高效的光催化剂是当务之急.氧化钛由于具有优异的物理化学稳定性、成本低廉、无毒性以及环境友好等优点,近年来被广泛关注.此外,空心球结构... 利用光催化技术将二氧化碳转化为化学燃料是缓解温室效应以及能源危机的理想途径之一.因此,开发高效的光催化剂是当务之急.氧化钛由于具有优异的物理化学稳定性、成本低廉、无毒性以及环境友好等优点,近年来被广泛关注.此外,空心球结构光催化剂具有短的载流子扩散距离、良好的光散射性以及较大的比表面积等优点,从而成为光催化二氧化碳还原最有潜力的候选材料.但纯的氧化钛空心球由于较快的光生载流子复合速率从而导致低的光催化效率.因此,为了应对这一挑战,我们尝试在氧化钛空心球表面负载助催化剂用以促进光生载流子的分离,从而提高光催化二氧化碳还原转换效率.在各种助催化剂中,贵金属被证明是有效的.然而,高成本以及稀缺性限制了贵金属的广泛应用.因此,有必要设计成本低廉的助催化剂替代品.石墨烯以其优异的导电性、较大的功函数以及来源丰富而备受关注.当石墨烯与n型半导体光催化剂结合在一起时,能够显著促进光生电子从半导体光催化剂向石墨烯的定向迁移,从而有效地抑制光生电子与空穴的复合.当石墨烯中掺杂氮元素时,石墨烯骨架中的电子密度会进一步提高,同时,氮原子中的孤对电子更加有利于石墨烯骨架中的电子传输.此外,氮掺杂石墨烯中不同的氮位点(吡碇氮、吡咯氮和石墨氮)作为路易斯碱位点,能够用以二氧化碳分子的吸附以及活化.然而,迄今为止,最常用的制备半导体/氮掺杂石墨烯纳米复合光催化剂的方法是在氮掺杂石墨烯表面生长半导体光催化剂.所制备的光催化剂与氮掺杂石墨烯之间界面接触有限,不利于光生载流子的快速传递与分离.此外,助催化剂和光催化剂之间建立高质量的界面接触可以有效地抑制光生电子与空穴的复合.因此,有必要绕开传统制备方法的弊端,从而设计与光催化剂之间具有大的接触面积和紧密的界面接触以及具有丰富活性位点的高质量氮掺杂石墨烯助催化剂.本文提出了一种新的策略,以吡啶分为氮掺杂石墨烯的前驱体,通过化学气相沉积方法在氧化钛空心球表面原位生长超薄氮掺杂石墨烯层(1〜2层).此外,在高温状态下,吡啶分子脱氢生成具有优异扩散性质的脱氢吡唳自由基气相分子.随着反应的进行,氧化钛表面的每个纳米颗粒基元表面都能够与吡碇分子充分接触,从而保障两者之间大面积以及紧密的界面接触.光催化二氧化碳还原性能测试结果表明,优化后的氧化钛/氮掺杂石墨烯空心球纳米复合材料的二氧化碳光催化总转化率(一氧化碳、甲醇和甲烷的总产率)为18.11μmolg^(-1)h^(-1),是空白氧化钛空心球的4.6倍和商业P25的10.7倍.高分辨透射电子显微镜、X射线光电子能谱以及拉曼光谱结果表明,成功构建了氧化钛与氮掺杂石墨烯之间紧密接触的界面.同时,氮掺杂石墨烯的引入能够显著增强复合光催化剂的表面光热效应以及氧化钛与氮掺杂石墨烯界面肖特基势垒的形成均有助于促进光催化二氧化碳还原反应的进行.因此,本文为石墨烯基光助催化剂的原位构建提供了一种行之有效的策略. 展开更多
关键词 超薄氮掺杂石墨烯层 化学气相沉积 紧密界面接触 光催化CO_(2)还原 吡啶氮位点
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考虑经济成本和环境影响的城市物流枢纽布局研究 被引量:1
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作者 胡博文 张建军 《上海管理科学》 2017年第1期85-88,共4页
在中国城市高速发展扩张的背景下,经济发展依旧是城市发展的重要目标,然而近年来城市环境受到越来越多的关注,对追求可持续的城市发展提出更高的要求。本文从城市物流整体角度,考虑城市物流的多层次、多类商品和多种运输工具,基于具体... 在中国城市高速发展扩张的背景下,经济发展依旧是城市发展的重要目标,然而近年来城市环境受到越来越多的关注,对追求可持续的城市发展提出更高的要求。本文从城市物流整体角度,考虑城市物流的多层次、多类商品和多种运输工具,基于具体指标量化了经济和环境等目标,分别建立城市物流枢纽布局模型,以上海市为实证研究对象,实例求解,验证模型的有效性。研究表明,经济成本与环境影响是相悖的,经济成本小,二氧化碳排放量大,反之亦然。 展开更多
关键词 城市物流 物流枢纽布局 碳排放
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Mild hypothermia combined with a scaffold of Ng Rsilenced neural stem cells/Schwann cells to treat spinal cord injury 被引量:12
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作者 Dong Wang Jinhua Liang +2 位作者 jianjun zhang Shuhong Liu Wenwen Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第24期2189-2196,共8页
Because the inhibition of Nogo proteins can promote neurite growth and nerve cell differentiation, a cell-scaffold complex seeded with Nogo receptor(Ng R)-silenced neural stem cells and Schwann cells may be able to im... Because the inhibition of Nogo proteins can promote neurite growth and nerve cell differentiation, a cell-scaffold complex seeded with Nogo receptor(Ng R)-silenced neural stem cells and Schwann cells may be able to improve the microenvironment for spinal cord injury repair. Previous studies have found that mild hypothermia helps to attenuate secondary damage in the spinal cord and exerts a neuroprotective effect. Here, we constructed a cell-scaffold complex consisting of a poly(D,L-lactide-co-glycolic acid)(PLGA) scaffold seeded with Ng R-silenced neural stem cells and Schwann cells, and determined the effects of mild hypothermia combined with the cell-scaffold complexes on the spinal cord hemi-transection injury in the T9 segment in rats. Compared with the PLGA group and the Ng R-silencing cells + PLGA group, hindlimb motor function and nerve electrophysiological function were clearly improved, pathological changes in the injured spinal cord were attenuated, and the number of surviving cells and nerve fibers were increased in the group treated with the Ng R-silenced cell scaffold + mild hypothermia at 34°C for 6 hours. Furthermore, fewer pathological changes to the injured spinal cord and more surviving cells and nerve fibers were found after mild hypothermia therapy than in injuries not treated with mild hypothermia. These experimental results indicate that mild hypothermia combined with Ng R gene-silenced cells in a PLGA scaffold may be an effective therapy for treating spinal cord injury. 展开更多
关键词 雪旺氏细胞 神经干细胞 脊髓损伤 亚低温 脚手架 治疗 NOGO受体 细胞支架
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Neural stem cell transplantation with Nogo-66 receptor gene silencing to treat severe traumatic brain injury 被引量:9
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作者 Dong Wang jianjun zhang +2 位作者 Jingjian Ma Yuan Mu Yinghui Zhuang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第10期725-731,共7页
Inhibition of neurite growth, which is mediated by the Nogo-66 receptor (NgR), affects nerve regeneration following neural stem cell (NSC) transplantation. The present study utilized RNA interference to silence NgR ge... Inhibition of neurite growth, which is mediated by the Nogo-66 receptor (NgR), affects nerve regeneration following neural stem cell (NSC) transplantation. The present study utilized RNA interference to silence NgR gene expression in NSCs, which were subsequently transplanted into rats with traumatic brain injury. Following transplantation of NSCs transfected with small interfering RNA, typical neural cell-like morphology was detected in injured brain tissues, and was accompanied by absence of brain tissue cavity, increased growth-associated protein 43 mRNA and protein expression, and improved neurological function compared with NSC transplantation alone. Results demonstrated that NSC transplantation with silenced NgR gene promoted functional recovery following brain injury. 展开更多
关键词 神经干细胞移植 NOGO 颅脑损伤 基因沉默 受体 生长相关蛋白 小分子干扰RNA 重型
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Transplantation of Nogo-66 receptor gene-silenced cells in a poly(D,L-lactic-co-glycolic acid) scaffold for the treatment of spinal cord injury 被引量:8
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作者 Dong Wang Yuhong Fan jianjun zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第8期677-685,共9页
Inhibition of neurite growth,which is in large part mediated by the Nogo-66 receptor,affects neural regeneration following bone marrow mesenchymal stem cell transplantation.The tissue engineering scaffold poly(D,L-lac... Inhibition of neurite growth,which is in large part mediated by the Nogo-66 receptor,affects neural regeneration following bone marrow mesenchymal stem cell transplantation.The tissue engineering scaffold poly(D,L-lactide-co-glycolic acid) has good histocompatibility and can promote the growth of regenerating nerve fibers.The present study used small interfering RNA to silence Nogo-66 receptor gene expression in bone marrow mesenchymal stem cells and Schwann cells,which were subsequently transplanted with poly(D,L-lactide-co-glycolic acid) into the spinal cord lesion regions in rats.Simultaneously,rats treated with scaffold only were taken as the control group.Hematoxylin-eosin staining and immunohistochemistry revealed that at 4 weeks after transplantation,rats had good motor function of the hind limb after treatment with Nogo-66 receptor gene-silenced cells plus the poly(D,L-lactide-co-glycolic acid) scaffold compared with rats treated with scaffold only,and the number of bone marrow mesenchymal stem cells and neuron-like cells was also increased.At 8 weeks after transplantation,horseradish peroxidase tracing and transmission electron microscopy showed a large number of unmyelinated and myelinated nerve fibers,as well as intact regenerating axonal myelin sheath following spinal cord hemisection injury.These experimental findings indicate that transplantation of Nogo-66 receptor gene-silenced bone marrow mesenchymal stem cells and Schwann cells plus a poly(D,L-lactide-co-glycolic acid) scaffold can significantly enhance axonal regeneration of spinal cord neurons and improve motor function of the extremities in rats following spinal cord injury. 展开更多
关键词 干细胞移植 脊髓神经元 L-乳酸 受体基因 NOGO 乙醇酸 治疗 NOGO-66受体
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