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草根NGO资金获取的困境及对策分析:对北京X基金会的个案研究
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作者 祝玉红 刘思 《中国社会工作研究》 CSSCI 2014年第1期170-186,共17页
近年来,我国各个领域的NGO层出不穷,它们在促进公民社会的发展和推动社会建设的同时也遭遇了自身发展的困境,这其中与NGO生存发展息息相关的资金获取问题尤其令人关注,然而目前较少研究者针对这一问题开展深入的个案研究。通过对X... 近年来,我国各个领域的NGO层出不穷,它们在促进公民社会的发展和推动社会建设的同时也遭遇了自身发展的困境,这其中与NGO生存发展息息相关的资金获取问题尤其令人关注,然而目前较少研究者针对这一问题开展深入的个案研究。通过对X基金会的参与式观察与访谈,本研究发现草根NGO的资金现状令人担忧,存在资金规模小、资金收入结构不合理、等资缺乏专业性等问题。本研究发现,草根NGO在资金获取方面的困境是结构性的而非偶然性的,与国家法团主义背景下的社会组织发展的逻辑过程相符合。针对这些困境,本研究从全力争取政府资金支持、强化民间捐款渠道以及提高等款专业性三个方面提出了建议。 展开更多
关键词 草根NGO 资金筹集 民间捐款
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A pulse of the Earth: A 27.5-Myr underlying cycle in coordinated geological events over the last 260 Myr 被引量:1
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作者 Michael R.Rampino Ken Caldeira yuhong zhu 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期236-242,共7页
We performed spectral analyses on the ages of 89 well-dated major geological events of the last 260 Myr from the recent geologic literature. These events include times of marine and non-marine extinctions,major ocean-... We performed spectral analyses on the ages of 89 well-dated major geological events of the last 260 Myr from the recent geologic literature. These events include times of marine and non-marine extinctions,major ocean-anoxic events, continental flood-basalt eruptions, sea-level fluctuations, global pulses of intraplate magmatism, and times of changes in seafloor-spreading rates and plate reorganizations. The aggregate of all 89 events shows ten clusters in the last 260 Myr, spaced at an average interval of ~ 26.9 Myr, and Fourier analysis of the data yields a spectral peak at 27.5 Myr at the ≥96% confidence level. A shorter period of ~ 8.9 Myr may also be significant in modulating the timing of geologic events.Our results suggest that global geologic events are generally correlated, and seem to come in pulses with an underlying ~ 27.5-Myr cycle. These cyclic pulses of tectonics and climate change may be the result of geophysical processes related to the dynamics of plate tectonics and mantle plumes, or might alternatively be paced by astronomical cycles associated with the Earth’s motions in the Solar System and the Galaxy. 展开更多
关键词 Global geological events Fourier analysis Cyclic pulses TECTONICS CORRELATIONS
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Spontaneous running wheel improves neuroprotection efficacy of ischemic postconditioning in mice following ischemia/reperfusion injury
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作者 Hong YE WeiWei Wang +10 位作者 Yu Ding XiaoLei Liu WenJI Jia WeiLi Luo HuiJuan Fan HongQun Zhou Jin Wang JianLong Ju DongMing Zhou TianHao Bao yuhong zhu 《BIOCELL》 SCIE 2018年第3期79-85,共7页
Ischemic postconditioning(IP)has been shown to provide protection for ischemia/reperfusion(IR)injury,but its efficacy is limited.In this study we hypothesized that spontaneous running wheel(RW)could improve neuroprote... Ischemic postconditioning(IP)has been shown to provide protection for ischemia/reperfusion(IR)injury,but its efficacy is limited.In this study we hypothesized that spontaneous running wheel(RW)could improve neuroprotection efficacy of IP for IR.We established mouse models of IR and showed that compared to Sham group,IR group had obvious brain infract and neurological dysfunction.In IR+IP group,brain infract and neurological dysfunction improved compared to IR group.However,in IR+IP+RW group brain infract and neurological dysfunction improved much better.TUNEL assay showed that IP but not RW significantly reduced the number of apoptotic cells after IR.However,the number of apoptotic cells was significantly reduced in RW+IP group.In addition,the levels of pro-apoptotic factors increased in IR group but significantly reduced in IR+IP+RW group,while the levels of antiapoptotic factors decreased in IR group but significantly increased in IR+IP+RW group.Moreover,in IR+IP+RW group,MDA level was further decreased and SOD level was further increased compared to IR+IP group.Finally,both PI3K inhibitor and STAT3 inhibitor significantly worsened brain infract and neurological dysfunction and promoted apoptosis in IR mice.In conclusion,RW combined with IP reduces brain infract and neurological dysfunction in mice after IR,and this is associated with enhanced anti-apoptotic and anti-oxidant benefits via the activation of PI3K and STAT3 pathways. 展开更多
关键词 Ischemic postconditioning ISCHEMIA/REPERFUSION running wheel apoptosis PI3K STAT3
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Azobenzene quaternary ammonium salt for photo-controlled and reusable disinfection without drug resistance
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作者 yuhong zhu Pengfei Li +5 位作者 Caikun Liu Mengqi Jia Yadong Luo Dengfeng He Chunyan Liao Shiyong Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第2期440-445,共6页
The abuse of antibiotics causes severe bacterial resistance, and the shortage of antibiotics has created a global public health crisis. This situation has prompted people to develop new antibacterial agents independen... The abuse of antibiotics causes severe bacterial resistance, and the shortage of antibiotics has created a global public health crisis. This situation has prompted people to develop new antibacterial agents independent of traditional antibiotics. Here, we created a series of photosensitive azobenzene-quaternary ammonium salt smart antibacterial agents by connecting azobenzene with amines with different chain lengths to improve the antibacterial selectivity of quaternary ammonium salt(QAS) and prevent the accumulation of active QAS in the environment. After trans-cis isomerization, the solubility of the title compound(compound 4) increased and the antibacterial property enhanced. The experimental results suggested that the antibacterial effect of compound 4 was significantly enhanced after 365 nm light irradiation, and it had photosensitive intelligent antibacterial activity and could be reused. Notably, we did not obtain any mutants of Staphylococcus aureus or Escherichia coli resistant to compound 4. In general,compound 4 has the advantages of high yield, photo-controllable antibacterial properties, reusability, and does not induce bacterial resistance. This photosensitive antibacterial compound provides a new idea for the construction of intelligent disinfectants and is expected to be a candidate for disinfectants in public facilities and medical architecture. 展开更多
关键词 AZOBENZENE Quaternary ammonium salt PHOTOSENSITIVITY REPEATABILITY Antibacterial agent
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Effects of Sc Addition and Annealing Treatment on the Microstructure and Mechanical Properties of the As-rolled Mg-3Li alloy 被引量:6
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作者 Guiying Sha Xiaoguang Sun +2 位作者 Teng Liu yuhong zhu Tao Yu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第8期753-758,共6页
The microstructures and mechanical properties of the as-rolled Mg-3Li and Mg-3Li-1Sc (wt%) alloys before and after annealing treatment have been investigated. Results show that the grains are refined evidently and t... The microstructures and mechanical properties of the as-rolled Mg-3Li and Mg-3Li-1Sc (wt%) alloys before and after annealing treatment have been investigated. Results show that the grains are refined evidently and the recrystallization temperature is improved for more than 100℃by adding 1 wt% Sc into the Mg-3Li alloy. After complete recrystallization, both the strength and ductility of the Mg-3Li alloy are improved evidently with the addition of minor Sc. The brittle fracture tendency of Mg-3Li-ISc alloy also reduces obviously. 展开更多
关键词 Mg-Li-Sc alloy ANNEALING Microstructure Mechanical properties
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Surface charge-convertible quaternary ammonium salt-based micelles for in vivo infection therapy 被引量:1
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作者 Dengfeng He Yifeng Tan +6 位作者 Pengfei Li Yadong Luo yuhong zhu Yunlong Yu Jiali Chen Ning Ning Shiyong Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第5期1743-1746,共4页
Quaternary ammonium salts(QASs) are excellent candidates for treating stubborn bacterial infections caused by biofilms due to their high sterilization efficiency and potential inhibition of the development of drug res... Quaternary ammonium salts(QASs) are excellent candidates for treating stubborn bacterial infections caused by biofilms due to their high sterilization efficiency and potential inhibition of the development of drug resistance.However,the inherent toxicity of QASs,including cytotoxicity,protein absorption and hemolysis,severely limits their applications in vivo.Herein,a charge-co nvertible quaternary ammonium salt-based micelle(QAS-SL@CM) was constructed by co-assembly of two amphiphiles with opposite charges and shell cross-linking strategy.The toxicity of the QAS-SL@CM could be greatly reduced towa rds human cells contrast to the corresponding QASs.By response to the acidic environment at infection sites,the surface charge of QAS-SL@CM could be immediately changed to positive and then target to negatively charged bacteria.Furthermo re,β-thiopropionate bonds on QAS-SL@CM could also be disintegrated under acid environment to release QASs to kill bacteria.Importantly,the QAS-SL@CM showed significant therapeutic effect in mice subcutaneous abscesses models without interference with normal cells.Therefore,a surface adaptive micelle constructed by charge-convertible strategy has been developed to ove rcome the cytotoxicity of QAS s,and could intelligently respond to the microenvironment of infected wound for in vivo infection therapy,which shows promising application in clinic. 展开更多
关键词 Quaternary ammonium salt Co-assembled micelle BIOFILM Biological safety In vivo infection
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Formation of coke in thermal cracking of jet fuel under supercritical conditions
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作者 yuhong zhu Caixiang YU +2 位作者 Zimu LI Zhentao MI Xiangwen ZHANG 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2008年第1期17-21,共5页
Continuous-flow reactor experiments were carried out to study coke formation from thermal crack-ing of home-made jet fuel RP-3 under supercritical con-ditions.The mechanism and precursor of coke forming were analyzed.... Continuous-flow reactor experiments were carried out to study coke formation from thermal crack-ing of home-made jet fuel RP-3 under supercritical con-ditions.The mechanism and precursor of coke forming were analyzed.The starting cracking temperature of RP-3 fuel was determined to be 471.8uC by differential scan-ning calorimetry(DSC).Temperature-programmed oxidation and scanning electron microscopy(SEM)characterizations of the stressed tubes showed that there are three different coke species including chemisorbed carbon,amorphous carbon and filamentous coke in the solid deposits.More than 90%of coke deposits are carried away by the supercritical fluid,which has strong capabilities of extraction for coke deposits and their pre-cursors.There were 17.1 wt-%of iron and 11.1 wt-%of chromium found on the coke surface detected by energy dispersive spectroscopy(EDS)which suggests carbure-tion on alloy.RP-3 fuel and its cracking liquids were analyzed by GC-MS,which showed that the content of alkyl benzene and alkyl naphthalene increased evidently in cracking liquids. 展开更多
关键词 COKE jet fuel thermal cracking SUPERCRITICAL EXTRACTION
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Large effective piezoelectric response from the spontaneously polarized surface layer in P(VDF-TrFE)arch films
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作者 Xinping Hu yuhong zhu Baojin Chu 《Journal of Advanced Dielectrics》 2022年第6期40-47,共8页
In this work,we show that a d_(33)~150 pC/N can be obtained in nonpoled poly(vinylidene fluoride trifluoroethylene)(P(VDF-TrFE))copolymer films with an arch structure.The copolymer films,which are often thought to be ... In this work,we show that a d_(33)~150 pC/N can be obtained in nonpoled poly(vinylidene fluoride trifluoroethylene)(P(VDF-TrFE))copolymer films with an arch structure.The copolymer films,which are often thought to be homogeneous,are in fact inhomogeneous in microstructure and physical properties after film fabrication.Although a large proportion of the copolymer film is nonpolar,as expected in a nonpoled ferroelectric film,the surface regions of the film are spontaneously polarized.We propose that inhomogeneous stress in the surface regions,which is either from the constraint of the substrate or skin layer effect formed during the film fabrication,generates a flexoelectric response and orients the spontaneous polarization of the ferroelectric film.As a result of the polar surface regions,the nonpoled films exhibit a piezoelectric response.The piezoelectric response is further amplified by the special arch structure of the films,leading to the observed large effective piezoelectric response.This study not only discovers the polar surface effect in ferroelectric polymer films,but also proposes an approach to design polymer materials with a strong piezoelectric response. 展开更多
关键词 Ferroelectric films dielectric polarization PIEZOELECTRICITY SURFACES
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