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Establishment of NaLuF_(4):15%Tb-based low dose X-PDT agent and its application on efficient antitumor therapy
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作者 Yi Tian Zhiguang Fu +7 位作者 Xiaosheng Zhu Chunjing Zhan Jinwei Hu Li Fan Chaojun Song Qian Yang Yu Wang Mei Shi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期599-610,共12页
X-ray excited photodynamic therapy(X-PDT)is the bravo answer of photodynamic therapy(PDT)for deep-seated tumors,as it employs X-ray as the irradiation source to overcome the limitation of light penetration depth.Howev... X-ray excited photodynamic therapy(X-PDT)is the bravo answer of photodynamic therapy(PDT)for deep-seated tumors,as it employs X-ray as the irradiation source to overcome the limitation of light penetration depth.However,high X-ray irradiation dose caused organ lesions and side effects became the major barrier to X-PDT application.To address this issue,this work employed a classic-al co-precipitation reaction to synthesize NaLuF_(4):15%Tb^(3+)(NLF)with an average particle size of(23.48±0.91)nm,which was then coupled with the photosensitizer merocyanine 540(MC540)to form the X-PDT system NLF-MC540 with high production of singlet oxygen.The system could induce antitumor efficacy to about 24%in relative low dose X-ray irradiation range(0.1-0.3 Gy).In vivo,when NLF-MC540 irradiated by 0.1 Gy X-ray,the tumor inhibition percentage reached 89.5%±5.7%.The therapeutic mechanism of low dose X-PDT was found.A significant increase of neutrophils in serum was found on the third day after X-PDT.By immunohistochemical staining of tumor sections,the Ly6G^(+),CD8^(+),and CD11c^(+)cells infiltrated in the tumor microenvironment were studied.Utilizing the bilat-eral tumor model,the NLF-MC540 with 0.1 Gy X-ray irradiation could inhibit both the primary tumor and the distant tumor growth.De-tected by enzyme linked immunosorbent assay(ELISA),two cytokines IFN-γand TNF-αin serum were upregulated 7 and 6 times than negative control,respectively.Detected by enzyme linked immune spot assay(ELISPOT),the number of immune cells attributable to the IFN-γand TNF-αlevels in the group of low dose X-PDT were 14 and 6 times greater than that in the negative control group,respectively.Thus,it conclude that low dose X-PDT system could successfully upregulate the levels of immune cells,stimulate the secretion of cy-tokines(especially IFN-γand TNF-α),activate antitumor immunity,and finally inhibit colon tumor growth. 展开更多
关键词 X-ray excited photodynamic therapy singlet oxygen low dose X-Ray irradiation efficient antitumor therapy anti-tumor immunity
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Industrialization,Efficiency and Social Housing:Sustainable Prefabrication for the Colombian Social and Cultural Context
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作者 Alejandro Restrepo Montoya 《Journal of Civil Engineering and Architecture》 2024年第2期92-99,共8页
This research aims to generate processes of industrialization and qualification of social housing in Colombia through prefabrication,low energy consumption and high environmental quality to reduce the current deficit ... This research aims to generate processes of industrialization and qualification of social housing in Colombia through prefabrication,low energy consumption and high environmental quality to reduce the current deficit and improve the quality of life in communities with fewer economic resources.Modular coordination and the use of materials with thermal behaviors,appropriate to the country’s climatic characteristics,reduce production costs,avoid waste and improve the architectural and environmental quality of social housing.Passive cooling strategies,such as controlling solar incursion and generating natural cross ventilation eliminate energy consumption and allow reaching desired standards of comfort.In a context in which traditional construction systems have still not resolved the social housing deficit in Colombia and which generate high costs for energy consumption in the search for thermal comfort,industrialized and efficient construction with high environmental quality provides solutions according to the economic,geographic,social and cultural context in Colombia. 展开更多
关键词 efficiency INDUSTRIALIZATION social housing SUSTAINABILITY low energy consumption
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Low organic matter abundance and highly efficient hydrocarbon generation of saline source rock in the Qaidam Basin,NW China
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作者 LI Guoxin ZHANG Bin +8 位作者 WU Kunyu WU Songtao WANG Xiaomei ZHANG Jing QI Xuening ZHANG Na XING Haoting XIAN Chenggang LIU He 《Petroleum Exploration and Development》 SCIE 2023年第5期1030-1044,共15页
The geochemical analysis and experimental simulation are comprehensively used to systematically study the hydrocarbon generation material,organic matter enrichment and hydrocarbon generation model of Paleogene source ... The geochemical analysis and experimental simulation are comprehensively used to systematically study the hydrocarbon generation material,organic matter enrichment and hydrocarbon generation model of Paleogene source rock in the Western Qaidam Depression,Qaidam Basin,NW China.Three main factors result in low TOC values of saline lacustrine source rock of the Qaidam Basin:relatively poor nutrient supply inhibits the algal bloom,too fast deposition rate causes the dilution of organic matter,and high organic matter conversion efficiency causes the low residual organic carbon.For this type of hydrogen-rich organic matter,due to the reduction of organic carbon during hydrocarbon generation,TOC needs to be restored based on maturity before evaluating organic matter abundance.The hydrocarbon generation of saline lacustrine source rocks of the Qaidam Basin is from two parts:soluble organic matter and insoluble organic matter.The soluble organic matter is inherited from organisms and preserved in saline lacustrine basins.It generates hydrocarbons during low-maturity stage,and the formed hydrocarbons are rich in complex compounds such as NOS,and undergo secondary cracking to form light components in the later stage;the hydrocarbon generation model of insoluble organic matter conforms to the traditional“Tissot”model,with an oil generation peak corresponding to Ro of 1.0%. 展开更多
关键词 Qaidam Basin Qaidam Western Depression Paleogene lower Ganchaigou Formation saline lake low TOC value shale oil dissolved organic matter high efficient hydrocarbon generation hydrocarbon generation model organic matter abundance
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Reasons and Solutions of the Time-consuming College English Teaching with Low Efficiency
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作者 刘荣臻 王晓静 《海外英语》 2016年第9期236-237,共2页
College English teaching has been regarded as time- consuming with low efficiency for a long time. This thesis proceeds with the entity of English education in China, deals with the main problems lying in the current ... College English teaching has been regarded as time- consuming with low efficiency for a long time. This thesis proceeds with the entity of English education in China, deals with the main problems lying in the current college English teaching from 3 perspectives, including the nation and society, teachers, and students, and provides 5 suggestions accordingly. 展开更多
关键词 COLLEGE English class teaching time-consuming with low efficiency REASON solution
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Experimental Study to Improve the Agronomic Efficiency of Low Grade Fine Size Rock Phosphate
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作者 Mahesh Ganesa Pillai Sumedh Sudhir Beknalkar Saket Sanjay Kashettiwar 《Journal of Agricultural Science and Technology(B)》 2013年第11期783-788,共6页
Soluble phosphate fertilizers have been preferably used in plant crop production. The cost of applying conventional water soluble phosphate fertilizer is high in developing countries since their manufacturing requires... Soluble phosphate fertilizers have been preferably used in plant crop production. The cost of applying conventional water soluble phosphate fertilizer is high in developing countries since their manufacturing requires importing high grade rock phosphate (RP). As a result, the use of indigenously available low-grade RP is gaining importance globally. In this study, experiments were carried out using clayey loamy alkaline soil to evaluate the agronomic efficiency of fine sized low grade RP with inorganic nitrogen fertilizers and it was further compared with that of soluble phosphate fertilizer (di-ammonium phosphate), Cicer arietinum was the test crops subjected to treatments of absolute control, di-ammonium phosphate and low grade RP with varying concentrations of ammonium sulphate or ammonium nitrate. The experiments were conducted during 2012-2013 in the bid to study the growth rate and the biomass of the crop. Tests were also performed to determine the residual effects of the fertilizers on the crops. The results revealed that the combined use of low grade RP and ammonium sulphate or ammonium nitrate, at 16 kg N/ha, resulted in an agronomic efficiency, in terms of biomass of plants, comparable to that of di-ammonium phosphate and was found to be a more attractive management option for resource-poor farmers. 展开更多
关键词 low grade RP FERTILIZER di-ammonium phosphate residual test relative agronomic efficiency.
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Discussion on the Influence of Overseas Financial Institutions’ Participation in Shares on the Operation Efficiency of China’s Banking Industry
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作者 Yu Guo 《Journal of Economic Science Research》 2019年第4期25-30,共6页
With the implementation of China’s reform and opening up policy and China’s successful accession to the World Trade Organization,more and more overseas financial institutions are participating in various Chinese ban... With the implementation of China’s reform and opening up policy and China’s successful accession to the World Trade Organization,more and more overseas financial institutions are participating in various Chinese banks,and the amount of investment is also expanding.Therefore,it is particularly important to study the impact of overseas financial institutions participating in the Chinese Banks on the operating efficiency of the China’s banking industry.Therefore,based on the previous literature research,this paper constructs six models to explore whether foreign financial institutions participate in shares and the impact of shareholding ratio on the operating efficiency of China’s banking industry. 展开更多
关键词 OVERSEAS FINANCIAL institutions PARTICIPATION in SHARES Operating efficiency
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On Efficiency of the Compulsive Institution in the Environment Governance
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作者 FanGenyao JiangLF 《Ecological Economy》 2005年第2期52-56,共5页
Limited by the condition of information, technology and natural elements, the compulsive institutions in the environment governance can not form a “hard constraint” to the individuals. Because of the individual'... Limited by the condition of information, technology and natural elements, the compulsive institutions in the environment governance can not form a “hard constraint” to the individuals. Because of the individual's speculative behaviors, the government's deviation from its environmental governance, and the non-cooperative game between individuals and the legal organization, the implementation of the compulsive institutions is not as good as being expected. Through analyzing the mechanism of the compulsive institutions, this paper puts forward some suggestions to enhance the efficiency of such institutions' implementation. 展开更多
关键词 compulsive institutions in the environment governance efficiency non-cooperative game.
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Multi-layer quasi-zero-stiffness meta-structure for high-efficiency vibration isolation at low frequency
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作者 Jiahao ZHOU Jiaxi ZHOU +3 位作者 Hongbin PAN Kai WANG Changqi CAI Guilin WEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第7期1189-1208,共20页
An easily stackable multi-layer quasi-zero-stiffness(ML-QZS)meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency.First,the distributed shape optimization method is us... An easily stackable multi-layer quasi-zero-stiffness(ML-QZS)meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency.First,the distributed shape optimization method is used to design the unit cel,i.e.,the single-layer QZS(SL-QZS)meta-structure.Second,the stiffness feature of the unit cell is investigated and verified through static experiments.Third,the unit cells are stacked one by one along the direction of vibration isolation,and thus the ML-QZS meta-structure is constructed.Fourth,the dynamic modeling of the ML-QZS vibration isolation metastructure is conducted,and the dynamic responses are obtained from the equations of motion,and verified by finite element(FE)simulations.Finally,a prototype of the ML-QZS vibration isolation meta-structure is fabricated by additive manufacturing,and the vibration isolation performance is evaluated experimentally.The results show that the vibration isolation performance substantially enhances when the number of unit cells increases.More importantly,the ML-QZS meta-structure can be easily extended in the direction of vibration isolation when the unit cells are properly stacked.Hence,the ML-FQZS vibration isolation meta-structure should be a fascinating solution for highly efficient vibration isolation performance at low frequency. 展开更多
关键词 quasi-zero stiffness(QZS) meta-structure high efficiency low frequency vibration isolation
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An Analysis of the Intrinsic Motivation and Supervision Efficiency of CPA Low-ballingin Audit Market of China
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作者 Linlin Huang Qingqing Zhou Zixin Chen 《Journal of Zhouyi Research》 2014年第4期48-52,共5页
关键词 监管部门 审计师 中国 效率分析 市场 CPA 上市公司 经济价值
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Research and Experience Reference on China’s Implementation of Low Carbon Strategy
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作者 Renrui Wang 《Journal of Geoscience and Environment Protection》 2024年第6期57-80,共24页
Economic development has brought about global greenhouse gas emissions, which in turn has brought about global climate change. This research paper aims to compare the strengths and weaknesses that China has demonstrat... Economic development has brought about global greenhouse gas emissions, which in turn has brought about global climate change. This research paper aims to compare the strengths and weaknesses that China has demonstrated in the implementation of its low-carbon city strategy and to summarise the valuable experience that China can provide to the world in the implementation of its low-carbon city strategy. This essay analyses in depth the advantages that China has shown in the areas of renewable energy use and government mechanisms, as well as the shortcomings that it has shown in the areas of eco-efficiency industrial structure and capacity upgrading. Then, the paper summarises the successful experiences of the Chinese government in the establishment of renewable energy use and governmental mechanisms, such as the local government’s ability to coordinate multiple sectors (industrial sector, energy sector, etc.) and the implementation of responsibilities. In comparison, the paper also further discusses that China’s implementation of a low-carbon strategy in the future may have more eco-efficiency, industrial structure and capacity upgrading. 展开更多
关键词 low Carbon LCCP Renewable Energy Government Mechanism ECO-efficiency Capacity Upgrade
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Effect of Low Light on the Characteristics of Photosynthesis and Chlorophyll a Fluorescence During Leaf Development of Sweet Pepper 被引量:23
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作者 SUI Xiao-lei MAO Sheng-li +2 位作者 WANG Li-hao ZHANG Bao-xi ZHANG Zhen-xian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第10期1633-1643,共11页
Low light stress is one of the main limiting factors which influence the production of sweet pepper under protected cultivation in China. In this experiment, two genotypes of sweet pepper, ShY (low light-tolerant gen... Low light stress is one of the main limiting factors which influence the production of sweet pepper under protected cultivation in China. In this experiment, two genotypes of sweet pepper, ShY (low light-tolerant genotype) and 20078 (low light-sensitive genotype), were used to study the effects of low light (photosynthetic photon flux density, PPFD was 75- 100 umol m-2 s-1, control 450-500 umol m-2 s-1) on photosynthesis during leaf development. The result indicated that under low light chlorophyll content, net photosynthetic rate (PN), photosynthetic apparent quantum efficiency (Фi) and carboxylation efficiency (CE) of sweet pepper leaves increased gradually and decreased after reaching the maximum levels. The time to reach the peak values for all the above parameters was delayed, whereas the light compensation point (LCP) decreased gradually along with leaf expansion. The decrease in maximum quantum yield of PS II (Fv/Fm) was not observed at any stages of the leaf development under low light condition, but the actual PS II efficiency under irradiance (ФPS II) was lower accompanied by an increased non-photochemical quenching (NPQ) in young and/or old leaves compared with mature leaves. The antenna thermal dissipation (D) was a main way of heat dissipation when young leaves received excessive light energy, while the decline in photosynthetic function in senescence leaf was mostly owing to the decrease in carbon assimilation capacity, followed by a significantly increased allocation of excessive energy (Ex). Compared with 20078, ShY could maintain higher PN, ФPS II and lower QA reduction state for a longer time during leaf development. Thus, in ShY photosynthetic efficiency and the activity of electron transport of PS II were not significantly affected due to low light stress. 展开更多
关键词 sweet pepper low light photosynthetic efficiency chlorophyll fluorescence leaf development
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The Lightweight Design of Low RCS Pylon Based on Structural Bionics 被引量:10
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作者 Hongjie Jiao,Yidu Zhang,Wuyi Chen Mechanical Engineering Design Centre,Beihang University,Beijing 100191,P.R.China 《Journal of Bionic Engineering》 SCIE EI CSCD 2010年第2期182-190,共9页
A concept of Specific Structure Efficiency (SSE) was proposed that can be used in the lightweight effect evaluation ofstructures.The main procedures of bionic structure design were introduced systematically.The parame... A concept of Specific Structure Efficiency (SSE) was proposed that can be used in the lightweight effect evaluation ofstructures.The main procedures of bionic structure design were introduced systematically.The parameter relationship betweenhollow stem of plant and the minimum weight was deduced in detail.In order to improve SSE of pylons, the structural characteristicsof hollow stem were investigated and extracted.Bionic pylon was designed based on analogous biological structuralcharacteristics.Using finite element method based simulation, the displacements and stresses in the bionic pylon were comparedwith those of the conventional pylon.Results show that the SSE of bionic pylon is improved obviously.Static, dynamic andelectromagnetism tests were carried out on conventional and bionic pylons.The weight, stress, displacement and Radar CrossSection (RCS) of both pylons were measured.Experimental results illustrate that the SSE of bionic pylon is markedly improvedthat specific strength efficiency and specific stiffness efficiency of bionic pylon are increased by 52.9% and 43.6% respectively.The RCS of bionic pylon is reduced significantly. 展开更多
关键词 lightweight design specific structure efficiency low RCS pylon bionic structure
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Effects of water application uniformity using a center pivot on winter wheat yield, water and nitrogen use efficiency in the North China Plain 被引量:5
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作者 CAI Dong-yu YAN Hai-jun LI Lian-hao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第9期2326-2339,共14页
In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain (NCP). The combined effects of water and nitrogen application uniformity on the gr... In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain (NCP). The combined effects of water and nitrogen application uniformity on the grain yield, water use efficiency (WUE) and nitrogen use efficiency (NUE) have become a research hotspot. In this study, a two-year field experiment was conducted during the winter wheat growing season in 2016–2018 to evaluate the water application uniformity of a center pivot with two low pressure sprinklers (the R3000 sprinklers were installed in the first span, the corresponding treatment was RS;the D3000 sprinklers were installed in the second span, the corresponding treatment was DS) and a P85A impact sprinkler as the end gun (the corresponding treatment was EG), and to analyze its effects on grain yield, WUE and NUE. The results showed that the water application uniformity coefficients of R3000, D3000 and P85A along the radial direction of the pivot (CUH) were 87.5, 79.5 and 65%, respectively. While the uniformity coefficients along the traveling direction of the pivot (CUC) were all higher than 85%. The effects of water application uniformity of the R3000 and D3000 sprinklers on grain yield were not significant (P>0.05);however, the average grain yield of EG was significantly lower (P<0.05) than those of RS and DS, by 9.4 and 11.1% during two growing seasons, respectively. The coefficients of variation (CV) of the grain yield had a negative correlation with the uniformity coefficient. The CV of WUE was more strongly affected by the water application uniformity, compared with the WUE value, among the three treatments. The NUE of RS was higher than those of DS and EG by about 6.1 and 4.8%, respectively, but there were no significant differences in NUE among the three treatments during the two growing seasons. Although the CUH of the D3000 sprinklers was lower than that of the R3000, it had only limited effects on the grain yield, WUE and NUE. However, the cost of D3000 sprinklers is lower than that of R3000 sprinklers. Therefore, the D3000 sprinklers are recommended for winter wheat irrigation and fertigation in the NCP. 展开更多
关键词 center pivot low pressure sprinkler water application uniformity winter wheat water and nitrogen use efficiency
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The Efficiency and Demands of the Italian Justice System
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作者 Marilene Lorizio Antonia Rosa Gurrieri 《Journal of Statistical Science and Application》 2015年第2期31-38,共8页
A high level of quality and efficiency in an economic system is extremely relevant for the growth of a country. This is particularly true in relation to the justice system. The aim of this work is to estimate the exte... A high level of quality and efficiency in an economic system is extremely relevant for the growth of a country. This is particularly true in relation to the justice system. The aim of this work is to estimate the extent to which the identified variables affect the length of civil proceedings, particularly with regard to the role of lawyers. 展开更多
关键词 quality and efficiency of the legal system Legal institutions
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The Information Efficiency of QFII's Investment in China's Capital Market
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作者 Sun Xianchao Zhao Xiaolei +1 位作者 Liu Xinran Dong Jianming 《Contemporary Social Sciences》 2021年第2期129-155,共27页
This paper takes stock price synchronization and price delay as indicators of information efficiency, and uses mixed cross-sectional data of listed companies into which Qualified Foreign Institutional Investors(QFII) ... This paper takes stock price synchronization and price delay as indicators of information efficiency, and uses mixed cross-sectional data of listed companies into which Qualified Foreign Institutional Investors(QFII) have made investments, to study the impact of QFII's investment behaviors on the information efficiency of China's stock market. The results show that QFII's investments can improve the information efficiency of China's stock market, but its impact is varied. The impact of QFII's investments on market information efficiency is more significant in bear markets than in bull markets, the impact on private enterprises is more significant than on state-owned enterprises, and the impact on Small and Medium Enterprises(SME) market is more significant than in main board market. Further research also finds that QFII has a certain threshold effect on the information efficiency of China's stock market. This research paper provides a problem-solving perspective for China's capital markets to achieve information efficiency through opening up, and at the same time warns against financial risks. 展开更多
关键词 Qualified Foreign institutional Investors stock price synchronization mixed cross-sectional data information efficiency
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On the Low-Efficiency in College English Teaching In China
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作者 高学军 《科技信息》 2010年第36期I0132-I0134,共3页
Great changes have taken place in college English teaching in China in recent decades.Different teaching theories have been introduced into English teaching in many colleges and universities.However,college English,as... Great changes have taken place in college English teaching in China in recent decades.Different teaching theories have been introduced into English teaching in many colleges and universities.However,college English,as one of the required courses,is faced with a lot of complaints and criticism from the students and teachers as well as the society.The low efficiency in college English teaching is one of the problems,which attract the attention of all those concerned.It is of great significance to find out why students spend so much time,money and energy on English learning but are still at loss how to use English for communication.Surely,teaching and learning English is not an easy job.It involves a number of complicated interrelated factors.The article is meant to discuss the factors that are closely related to the low-efficiency in college English teaching in china,such as education notion,usage of textbooks,teacher quality as well as students motivations,aiming to make people have a clear idea of the problem so that some things can be done to improve the quality and efficiency of college English teaching in China. 展开更多
关键词 中国 英语 高校 学习方法
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Differentiation of Barley Genotypes with High Phosphorus Efficiency under Low Phosphorus Stress 被引量:2
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作者 杨涛 何金宝 +3 位作者 曾亚文 普晓英 杨树明 杜娟 《Agricultural Science & Technology》 CAS 2013年第11期1615-1619,共5页
[Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to exp... [Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to explore the relationship be-tween agronomic traits and row type with phosphorus efficiency. [Method] Under available phosphorus mass fractions of 1.32 and 36.6 mg/kg, 172 barley varieties, including 79 two-rowed foreign barley, 22 multiple-rowed foreign barley, 58 two-rowed Chinese barley and 13 multiple-rowed Chinese barley, were selected to com-pare differences in phosphorus efficiency-related agronomic traits. Plant height, spike length, number of unfil ed grains, number of unfil ed grains, main panicle weight, to-tal panicle weight, total stem weight, weight of aerial part and heading stage were surveyed for statistical analysis. [Result] The results showed that, various agronomic traits were larger under fertilization condition than under non-fertilization condition ex-cept number of unfil ed grains and heading stage. Plant high, spike length, weight of aerial part and heading stage varied greatly under non-fertilization condition; number of fil ed grains, number of unfil ed grains and total stem weight varied greatly under fertilization condition. In two-rowed barley, plant height and number of fil ed grains of Chinese varieties were higher than those of foreign varieties, while other agronomic traits such as spike length, number of unfil ed grains, main panicle weight, total panicle weight, total stem weight, weight of aerial part and heading stage of foreign varieties were higher than those of Chinese varieties. Spike length and weight of aerial part in multiple-rowed and two-rowed foreign barley were higher than those in Chinese barley. In multiple-rowed barley, plant height, number of unfil ed grains, total panicle weight and total stem weight of foreign varieties were higher under non-fer-tilization condition and lower under fertilization condition compared with those of Chi-nese varieties; number of fil ed grains, main panicle weight and heading stage of foreign varieties were lower under non-fertilization condition and higher under fertil-ization condition compared with those of Chinese varieties. [Conclusion] Heading stage, number of fil ed grains, number of unfil ed grains and total stem weight are more sensitive to phosphorus efficiency. Multiple-rowed barley is more sensitive to phosphorus efficiency than two-rowed barley. 展开更多
关键词 low phosphorus stress BARLEY High phosphorus efficiency GENOTYPE Agronomic traits
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Research on Experimental and Application for the High Efficient Enrichment of the Low-grade Precious Metal Materials
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作者 FAN Xingxiang FU Guangqiang +6 位作者 DONG Haigang WU Yuedong LIU Yang ZHAO Jiachun WU Xiaofeng LI Bojie TONG Weifeng 《贵金属》 CAS CSCD 北大核心 2012年第A01期11-17,共7页
On the basis of reviewing the progress in the high efficient enrichment from secondary resources of low grade precious metals at home and abroad, a process route of the high efficient enrichment precious metals from s... On the basis of reviewing the progress in the high efficient enrichment from secondary resources of low grade precious metals at home and abroad, a process route of the high efficient enrichment precious metals from secondary resources of low-grade metals by adding iron oxide as the trapping agent, reducing agent, additive, mixing uniformly and grinding, pelletizing, reduction, grinding and separation, and selectively acid leaching iron has been put forward in this paper. The experiments of reduction, grinding and separation, and selectively acid leaching iron were carried out mainly. Under the decided experiment parameters and conditions, iron generated during the reduction can trap precious metals during reduction, high active alloy powders were obtained from the reduced products by grinding and separation, the concentration of precious metals was obtained by acid leaching high active alloy powders. The better enrichment effect was obtained by adopting the technical route of processing. Other low grade noble metal materials and enrichment ratio of precious metals from the materials to acid products was high through acid leaching. This process has the advantages of simple process, environmental-friendly, strong adaptability of raw materials, high concentration ratio, which was regarded as a kind of the general efficient enrichment technology of low grade precious metal materials. 展开更多
关键词 low-grade precious metals secondary resources the high efficient enrichment REDUCTION grinding and separation acid leaching
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Analysis of Phosphorus Nutrition Efficiency of Soybean Genotypes with Different Phosphorus Efficiency at Blooming Stage under Low Phosphorus Stress 被引量:2
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作者 张彦丽 《Agricultural Science & Technology》 CAS 2012年第12期2544-2548,共5页
[Objective] This study aimed to investigate the phosphorus nutrition effi- ciency of different soybean genotypes at blooming stage under low phosphorus stress. [Method] By using four "low phosphorus efficiency" soyb... [Objective] This study aimed to investigate the phosphorus nutrition effi- ciency of different soybean genotypes at blooming stage under low phosphorus stress. [Method] By using four "low phosphorus efficiency" soybean genotypes (D03, D05, D17 and D18) and four "high phosphorus efficiency" soybean genotypes (D31, D34, D37 and D38) as experimental materials, soil culture experiment was conduct- ed with two treatments of high phosphorus (+P) and low phosphorus (-P), to analyze the relationship between phosphorus content, phosphorus uptake, phosphorus use efficiency and phosphorus efficiency of soybean genotypes with different phos- phorus efficiency. [Result] Under low phosphorus conditions, four soybean genotypes with high phosphorus efficiency showed significant advantage in phosphorus uptake at seedling stage, to be specific, D34 showed relatively high phosphorus absorption capacity but no advantage in adaptability of phosphorus use efficiency, while only D37 showed relatively high phosphorus absorption capacity and phosphorus use ca- pacity. Correlation analysis and path analysis showed that the level of phosphorus efficiency of soybean at blooming stage under (-P) and (+P) treatments was mainly determined by phosphorus absorption capacity, and that under (-P) treatment was significantly greater than (+P) treatment. Phosphorus uptake and phosphorus use ef- ficiency under (-P) and (+P) treatments both showed great direct effects on phos- phorus efficiency, and phosphorus uptake made greater contribution; however, the indirect effects were relatively low, Under low phosphorus stress, the mechanisms for various soybean genotypes with high phosphorus efficiency to adapt to low phospho- rus stress were different, and phosphorus absorption efficiency (phosphorus uptake) was the main variation source of the phosphorus efficiency of various soybean genotypes at blooming stage. [Conclusion] This study revealed the contribution made by phosphorus absorption efficiency and phosphorus use efficiency to phosphorus efficiency of soybean. 展开更多
关键词 SOYBEAN low phosphorus stress Phosphorus efficiency Absorption ef- ficiency Use efficiency
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移民网络、制度距离与中国企业OFDI效率
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作者 赵家章 周凡煜 连慧君 《北京工商大学学报(社会科学版)》 北大核心 2024年第4期16-29,共14页
提高企业对外直接投资(OFDI)效率是中国推进高水平对外开放的重要路径之一。基于2003—2021年中国A股上市公司数据,实证分析了移民网络对中国企业OFDI效率的影响及其机制。研究发现,移民网络显著提升了中国企业OFDI效率,且通过降低交易... 提高企业对外直接投资(OFDI)效率是中国推进高水平对外开放的重要路径之一。基于2003—2021年中国A股上市公司数据,实证分析了移民网络对中国企业OFDI效率的影响及其机制。研究发现,移民网络显著提升了中国企业OFDI效率,且通过降低交易成本、提高合同执行效率、弥合文化距离促进了企业OFDI效率提升。异质性分析结果表明,移民网络对中国企业OFDI效率的提升作用仅显著存在于非国有企业、绿地投资企业以及向非接壤国家直接投资的企业中,且在向发展中国家直接投资的企业中更显著。进一步研究发现,制度距离在移民网络与中国企业OFDI效率的关系中发挥了调节作用,制度距离缩小,会强化移民网络对企业OFDI效率的提升作用。因此,政府应加强移民网络建设,加大对OFDI企业的政策支持力度,缩小双边制度距离,企业则应充分利用移民网络降低OFDI风险及不确定性,进而促进中国企业提升OFDI效率。 展开更多
关键词 移民网络 企业ofDI效率 制度距离 文化距离 社会网络分析
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