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Transactions of Nonferrous Metals society of china 2020年第10期30卷 2792-2801页

作者： Fang-xu LI Xiao-tong ZHOU ri-xiao LIN Guangdong Academy of sciences Guangzhou 510650China Guangdong Institute of Resources comprehensive Utilization Guangzhou 510650China state Key Laboratory of Rare Metals separation and comprehensive Utilization Guangzhou 510650China Guangdong Provincial Key Laboratory of Development and comprehensive Utilization of Mineral Resources Guangzhou 510650China

A novel collector 1-(2-hydroxyphenyl)hex-2-en-1-one oxime(HPHO)was synthesized from 2-hydroxy acetophenone and *** flotation performance and adsorption mechanism to malachite were investigated by flotation test,zeta potential,Fourier transform infrared(FTIR)and X-ray photoelectron spectroscopy(XPs)analysis *** with benzohydroxamic acid(BA),1-(2-hydroxyphenyl)ethan-1-one oxime(HPEO)and sodium isobutyl xanthate(sIBX),HPHO exhibited excellent collecting power to malachite without additional reagents,such as Na2s regulator and methyl isobutyl carbinol(MIBc)*** of zeta potential indicated that HPHO was coated on malachite surfaces through a chemisorption *** and XPs data gave clear evidence for the formation of cu−oxime complex on malachite surfaces after HPHO adsorption through the linkage between c=c,—OH,N—OH group and cu species.

关键词： malachite flotation collector oxime adsorption mechanism

Damage characteristics of thermally treated granite under uniaxial compression: Insights from active and passive ultrasonic techniques

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Journal of central south University 2022年第12期29卷 4078-4093页

作者： GUO Pei WU shun-chuan JIANG ri-hua ZHANG Guang Key Laboratory of Ministry of Education for Efficient Mining and safety of Metal Mines(University of science and Technology Beijing) Beijing 100083China Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093China school of civil Engineering Shandong UniversityJinan 250061China

To explore the effects of thermal treatment on cracking processes in granite, granite samples were thermally treated at 25-400 ℃ and then loaded under uniaxial compression. Active ultrasonic testing and passive acoustic emission(AE) monitoring were combined to monitor the damage characteristics of the samples. The uniaxial compression strength(Ucs) of the sample treated at 200 ℃ shows no apparent change compared with that of the nonheated sample, while the Ucs increases at 300 °c and decreases at 400 ℃. As the temperature increases from 25 to 400 ℃, the initial P-wave velocity(Vp) decreases gradually from 4909 to 3823 m/s, and the initial Vpanisotropy ε increases slightly from 0.03 to 0.09. As the axial stress increases, ε increases rapidly in the crack closure stage and unstable cracking stage. The attenuation of ultrasonic amplitude spectra also shows an obvious anisotropy. Besides, the main location magnitude of AE events decreases after thermal treatment, and low-frequency AE events and high-amplitude AE events increasingly occur. However, there is insufficient evidence that the treatment temperature below 400 ℃ has a significant effect on the temporal characteristics, source locations, and b-values of AE.

关键词： uniaxial compression thermal treatment acoustic emission ultrasonic b-value dominant frequency

An Indentation Method for Nanoprecision Measurement of Diamond Tool Edge Radius

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厦门大学学报（自然科学版） 2002年第S1期41卷 98-99页

作者： X P Li M Rahman K Liu K s Neo c c chan Department of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of Singapore SingaporeSingaporeSingaporeProcess Technology Division Gintic Institute of Manufacturing Technology Si ngaporeSingaporeSingapore

In ductile mode cutting of brittle materials using di amond tools, such as ductile cutting of silicon and quartz for wafer fabrication , one of the key conditions for achieving ductile chip formation is to get the r ight ratio of tool cutting edge radius to the undeformed chip thickness. It has been shown that the undeformed chip thickness has to be in the order of nanomete rs and that the tool cutting edge radius has to be smaller than the undeformed c hip thickness. Therefore, nanoprecision measurement of diamond cutting tools has become a key issue for ductile mode cutting of brittle materials. In this paper , a non-destructive nanoprecision measurement method for diamond tool cutting e dge radius is presented. The basis of the method is that the exact profile of th e tool cutting edge can be perfectly copied by indenting the tool cutting edge o n the surface of a rigid-perfect plastic material, and that the copy of the pro file can be measured at nanoprecision level. Ideally, the first aspect of th e method is to make a perfect copy of the tool cutting edge profile by indentati on on the surface of a rigid-perfect plastic material which has no elastic spri ng back, so that a true copy of the tool cutting edge is maintained for subseque nt measurement. since no rigid-perfect plastic material can be found in realit y, actual materials of rigid-elastic-plastic nature have to be used for the in dentation in the measurement method, and the material elastic error compensation coefficients have to be determined to cancel out the effect of elastic spring b ack. For the minimization of error compensation, criteria for the selection of t he optimal materials for the indentation measurement are found to be: 1) high ri gidity and high density, 2) large Young’s elastic modulus, and 3) low yield strength. One of such materials identified is copper. The second aspect of the method is to measure the radius of the indented profile on the surface of the ma terial. This can be ach

关键词： nanoprecision measurement indentation diamond tool cutting edge radius ductile mode cutting

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Wc-Ni基硬质合金的光固化增材制造

稀有金属与硬质合金 2024年第2期52卷 76-88页

作者：刘展赫陈子航王日初彭超群时凯华周科朝马格达西·什洛莫王小锋中南大学材料科学与工程学院湖南长沙410083 中钨高新材料股份有限公司湖南株洲412000 中南大学粉末冶金国家重点实验室湖南长沙410083 耶路撒冷希伯来大学化学研究所耶路撒冷91904

采用光固化增材制造(3D打印)技术制备Wc-Ni基硬质合金,研究了浆料配比和增材制造工艺参数对浆料流变性能和固化性能的影响以及Wc-Ni基硬质合金的性能。结果表明:当浆料固含量为40%(体积分数)、分散剂为ZN-1344且加入量为粉体质量的2%时,... 详细信息

采用光固化增材制造(3D打印)技术制备Wc-Ni基硬质合金,研究了浆料配比和增材制造工艺参数对浆料流变性能和固化性能的影响以及Wc-Ni基硬质合金的性能。结果表明:当浆料固含量为40%(体积分数)、分散剂为ZN-1344且加入量为粉体质量的2%时,Wc-Ni浆料的流变性能满足增材制造工艺需求,当剪切速率为100 s^(-1)时,浆料黏度为2.718 Pa·s;该浆料的最大单层固化厚度可达144μm,对应工艺参数为0.01 mm线间距、90%激光功率和2 000 mm/s扫描速度;采用响应曲面法拟合数据获得的浆料单层固化厚度计算模型,计算值与实际值误差为3.4%,可起理论预测作用;光固化增材制造Wc-15%Ni硬质合金的密度和相对密度最高,分别为13.51 g/cm^(3)和96.5%,加入1%晶粒长大抑制剂cr_(3)c_(2)后,硬质合金维氏硬度显著提高,达到945 HV_(30),接近同等Ni含量但不含有cr_(3)c_(2)的传统硬质合金硬度。

关键词： Wc-Ni基硬质合金光固化增材制造 3D打印响应曲面法晶粒长大抑制剂复杂结构

sUPPREssOR OF VAriEGATION4, a New var2 suppressor Locus, Encodes a Pioneer Protein that Is Required for chloroplast Biogenesis

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Molecular Plant 2011年第2期4卷 229-240页

作者： Fei Yu ung-soon Park Xiayan Liu Andrew Foudree Aigen Fu Marta Powikrowska Anastassia Khrouchtchova Poul Erik Jensen Jillian N. Kriger Gordon ri Gray steven R. Rodermel college of Life sciences Northwest A&F University Yangling Shaanxi 712100 People's Republic of China Department of Plant and Microbial Biology University of California Berkeley Berkeley CA 94720 USA Department of Genetics Development and Cell Biology iowa State University 253 Bessey Hall Ames IA 50011 USA Department of Plant Biology and Biotechnology Faculty of Life Sciences University of Copenhagen Thorvaldsensvej 40 DK-1871 Frederiksberg C Denmark Department of Plant sciences University of Saskatchewan Saskatoon Saskatchewan S7N 5A8 Canada

VAR2 is an integral thylakoid membrane protein and a member of the versatile FtsH class of metalloproteases in prokaryotes and eukaryotes. Recessive mutations in the VAR2 locus give rise to variegated plants （var2） that contain white sectors with abnormal plastids and green sectors with normal-appearing chloroplasts. In a continuing effort to isolate second-site suppressors of var2 variegation, we characterize in this report ems2505, a suppressor strain that has a virescent phenotype due to a missense mutation in At4g28590, the gene for a pioneer protein. We designated this gene sVR4 （for sUPPREssOR OF VAriEGATION4） and the mutant allele in ems2505 as svr4-1. We demonstrate that sVR4 is located in chloroplasts and that svr4-1 single mutants are normal with respect to chloroplast anatomy and thylakoid membrane protein accumulation. However, they are modestly impaired in several aspects of photochemistry and have enhanced non-photochemical quenching （NPQ） capacity. A T-DNA insertion allele of sVR4, svr4-2, is seedling-lethal due to an early blockage of chloroplast development. We conclude that sVR4 is essential for chloroplast biogenesis, and hypothesize that sVR4 mediates some aspect of thylakoid structure or function that controls NPQ. We propose that in the suppressor strain, photoinhibitory pressure caused by a lack of VAR2 is ameliorated early in chloroplast development by enhanced NPQ capacity caused by reduced sVR4 activity. This would result in an increase in the number of chloroplasts that are able to surmount a threshold necessary to avoid photo-damage and thereby develop into functional chloroplasts.

关键词： Arabidopsis chloroplast biogenesis non-photochemical quenching (NPQ) photo-damage suppressor strain variegation

Exposure of Mercury from Gold Ming Area: A case study in Tendo and Aby Lagoon in côte d’Ivoire

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Journal of Environmental Protection 2022年第9期13卷 613-627页

作者： stéphane Jean claon serge Kouakou Kouassi séka Arsène M’bassidje Laurent Kipré séri Luc Kouakou Kouadio Joseph Allico Djaman Public Health and Hydrology Laboratory Félix Houphou&euml t-Boigny University Abidjan C&ocirc te d’Ivoire Water Quality control and Analysis Laboratory National Drinking Water Office Abidjan C&ocirc te d’Ivoire Biology and Health Laboratory Félix Houphou&euml t-Boigny University Abidjan C&ocirc te d’Ivoire Environmental sciences Laboratory Nanguy Abrogoua University Abidjan C&ocirc te d’Ivoire Department of Medical and Fundamental Biochemistry Institut Pasteur of C&ocirc te d’Ivoire Abidjan C&ocirc te d’Ivoire

Lagoons of West African countries are seriously threatened by rapid artisanal and small-scale gold mining (AsGM) that exposes lagoons to mercury pollution. In this study, the mercury level in the sediments of the Tendo and Aby lagoons in côte d’Ivoire had been evaluated. A total of 87 samples from 25 stations located on Tendo and Aby lagoons were analyzed by atomic fluorescence spectrometry. The mean Hg concentrations obtained in the sediments of Tendo and Aby lagoons were 0.89 ± 0.26 mg⋅kgsup>-1sup> and 0.70 ± 0.18 mg⋅kgsup>-1sup>, respectively. Hg concentrations evaluated in the bays of Tendo and Aby during the dry season were 1.38 ± 0.45 mg⋅kgsup>-1sup> and 1.07 ± 0.31 mg⋅kgsup>-1sup>, respectively. The minimum and maximum total Hg concentrations in the sediments from 25 stations were 0.04 and 3.56 mg⋅kgsup>-1sup>, respectively. Mercury contamination in lagoons during AsGM poses risks of pollution for the lagoon ecosystem and also poses health risks for the population living near these lagoons.

关键词： AsGM Mercury sediments côte d’Ivoire Pollution

仿生态条件下星洲红鱼(singapore red tilapia)和奥尼罗非鱼(Oreochromis niloticus)生长和肌肉营养特性的比较研究

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海洋与湖沼 2022年第1期53卷 141-149页

作者：林祥日厦门海洋职业技术学院海洋生物学院福建厦门361100

为比较星洲红鱼(singapore red tilapia)和奥尼罗非鱼(Oreochromis niloticus)的生长和肌肉营养特性,实验利用两种鱼的不同体色将其混养在同一池塘中,在相同的环境条件和养殖管理下研究其生长特性,并分析肌肉营养成分。结果表明:两种罗... 详细信息

为比较星洲红鱼(singapore red tilapia)和奥尼罗非鱼(Oreochromis niloticus)的生长和肌肉营养特性,实验利用两种鱼的不同体色将其混养在同一池塘中,在相同的环境条件和养殖管理下研究其生长特性,并分析肌肉营养成分。结果表明:两种罗非鱼生长在前60 d无差异,60 d后星洲红鱼的体长、体质量日增长和特定生长率均大于奥尼罗非鱼,且差异显著(PsFA和∑UFA分别为28.03%和28.60%,63.87%和61.38%,各脂肪酸含量除c14:0和c18:2外,其他含量差异不显著。研究表明,星洲红鱼和奥尼罗非鱼生长快、营养丰富、食用价值高,是优质淡水鱼类养殖品种,其中星洲红鱼含肉率高,生长快,养殖效益明显。

关键词：星洲红鱼(singapore red tilapia) 奥尼罗非鱼(Oreochromis niloticus) 生长肌肉营养评价

A GIs tool for infinite slope stability analysis(GIs-TIssA)

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Geoscience Frontiers 2021年第2期12卷 756-768页

作者： Rüdiger Escobar-Wolf Jonathon D.sanders c.L.Vishnu Thomas Oommen K.s.sajinkumar Department of Geological and Mining Engineering and sciences Michigan Technological UniversityHoughtonMIUSA Department of Geology University of KeralaThiruvananthapuram 695581KeralaIndia

Landslides are one of the most common and a destructive natural hazard in mountainous terrain and thus evaluating their potential locations and the conditions under which they may occur is crucial for their hazard *** landslide occurrence in soil and regolith covered slopes are often modeled using the infinite slope model,which characterizes the slope stability in terms of a factor of safety(Fs) *** approaches have been followed to also assess and propagate uncertainty through such ***(2004) introduced the use of the First Order second Moment(FOsM) method to propagate input uncertainty through the infinite slope model,further developing the model and implementing it in the PIsA-m software package(Haneberg,2007).Here we present an ArcPy implementation of PIsA-m algorithms,which can be run from Esri ArcMap in an entirely consistent georeferenced framework,and which we call "GIs Tool for Infinite slope stability Analysis"(GIs-TIssA).Users can select between different input options,e.g.,following a similar input style as for PIsA-m,i.e., using an *** parameters input file,or providing each input parameter as a raster or constant value,through the program graphic user *** outputs can include Fs mean and standard deviation estimates,the probability of failure(Fs ri) calculation for *** the same seismic analysis approach as in PIsA-m, the Newmark acceleration can also be done,for which raster files of the mean,standard deviation,probability of exceedance,and ri are also *** of the code is done by replicating the results obtained with the PIsA-m code for different input options,within a 10-5 relative *** carlo modeling is also applied to validate GIs-TIssA outputs,showing a good overall correspondence.A case study was performed for Kannur district,Kerala,India,where an extensive landslide databa se for the year 2018 was available.81.19% of the actual

关键词： Landslides GIs-TIssA PIsA-m FOsM Factor of safety

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涂挂法电磁改性水泥基复合材料的吸波性能

华南理工大学学报（自然科学版） 2013年第2期41卷 135-140页

作者：国爱丽高日巴恒静北京交通大学土木建筑工程学院北京100044 哈尔滨工业大学土木工程学院黑龙江哈尔滨150090

为了获得具有吸波性能的水泥基复合材料,首先,采用涂挂法对闭孔珍珠岩和粉煤灰漂珠表面进行电磁改性.然后,通过测量各改性珍珠岩和粉煤灰漂珠与水泥基材料复合后材料的电磁波反射率,获得了吸波效果稳定的涂挂材料比例.最后,对比研究了... 详细信息

为了获得具有吸波性能的水泥基复合材料,首先,采用涂挂法对闭孔珍珠岩和粉煤灰漂珠表面进行电磁改性.然后,通过测量各改性珍珠岩和粉煤灰漂珠与水泥基材料复合后材料的电磁波反射率,获得了吸波效果稳定的涂挂材料比例.最后,对比研究了改性珍珠岩水泥基复合材料和石墨(或铁氧体)复合水泥基材料在s～c波段和X～Ku波段的电磁波反射率,并通过扫描电镜观测改性珍珠岩的微观结构.结果表明:石墨和铁氧体在连续釉化面与特殊蜂窝结构相间的珍珠岩颗粒表面分布均匀,形成有效谐振腔吸波体;涂挂法改性闭孔珍珠岩能有效提高水泥基材料的吸波性能,拓宽-10dB带宽.

关键词：水泥基复合材料涂挂法电磁改性吸波性能闭孔珍珠岩粉煤灰漂珠

Planarized Polymer Acceptor Featuring High Electron Mobility for Efficient All-Polymer solar cells

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chinese Journal of Polymer science 2022年第8期40卷 968-978,I0011页

作者： Feng Liu ri sun cheng-Yu Wang Liang Zhou Wen-Li su Qi-Hui Yue shuai sun Wu-Yue Liu Hai-Jun Fan Wen-Kai Zhang Yun-Long Guo Li-Heng Feng Xiao-Zhang Zhu school of chemistry and chemical Engineering Shanxi UniversityTaiyuan030006China Beijing National Laboratory for Molecular sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing100190China Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum StudiesBeijing Normal UniversityBeijing100875China University of chinese Academy of sciences Beijing100049China

significant progress has been achieved for all-polymer solar cells(APscs)in the last few years by the use of polymerized small molecular acceptors(PsMAs).Developing high electron mobility polymer acceptors has been considered a feasible solution to further improve the photovoltaic performance of APscs and fabricate thick film devices,which contributed to roll-to-roll printing *** this work,we designed and synthesized PsV,an A-DA’D-A small molecule acceptor-based PsMA with the vinyl group as a bridged linkage to reduce the steric hindrance between the 1,1-dicyanomethylene-3-indanone(Ic)terminal *** comparison with the c-c bond linked polymer acceptor Ps,PsV exhibits an almost planar conjugated framework and well-ordered molecular stacking in the thin ***,PsV exhibits superior n-type semiconducting properties with high electron mobility of up to 0.54 cm^(2)·V^(−1)·s^(−1),which is the highest value among reported *** utilizing PM6 as a polymer donor,PsV-based blend forms a favorable nanomorphology and exhibits high and well-balanced hole/electron mobilities,which is beneficial for exciton separation and charge ***,APscs based on PM6:PsV achieved high power conversion efficiencies of up to 15.73%,with a simultaneously realized high Voc of 0.923 V,Jsc of 23.2 mA·cm^(-2),and FF of *** superior features enable PsV with excellent thickness-insensitive properties and over 13%PcE was obtained at 300 *** the best of our knowledge,the high PcE of 15.73%with excellent electron mobility of 0.54 cm^(2)·V^(−1)·s^(−1)is the highest values reported for *** results point to the great significance of developing polymer acceptors with a high electron mobility for boosting the performance of APscs.

关键词： All-polymer solar cells Polymerized small molecular acceptors Planarization Electron mobility Thick film organic solar cells