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Loading capacity and emulsification phenomena of HREE extraction by dialkylphosphinic acids with different β,γ,δ-substituents

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Journal of Rare Earths 2024年第1期42卷 191-199,I0007页

作者： Junlian Wang Guodong Xu wen Xu Jianguo Cui Yufu chen Ziyong Chang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines Beijing100083China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China

The relationship between dialkylphosphinic acid structure and their loading capacity for HREEs and emulsification phenomena has rarely been *** this paper,we took Lu extraction as an example to study the effect of β,γ,δ-substituents of dialkylphosphinic acids on their loading capacity and anti-emulsification performance for *** discuss conveniently,the dialkylphosphinic acids were classified into two groups:β-substituent group(P208,INET-1,P218,USTB-1 and P227)and γ,δ-substituent group(P218,P2132 and Cyanex 272).For β-substituent group extractants,their loading capacities are in the order P208(299.7 mg/L)≈INET-1(299.5 mg/L)>P218(270.8 mg/L)>>USTB-1(163.1 mg/L)>P227(151.4 mg/L),while their anti-emulsification/gelation performances are just in the opposite order P227>USTB-1>P218>P208≈INET-1 under the studied *** γ,δ-substituent group extractants,their loading capacities are in the order P218(270.8 mg/L)>P2132(192.3 mg/L)>Cyanex272(131.7 mg/L),while the anti-emulsification performance of P218 is better than those of P2132 and Cyanex *** loading capacity data given in the parentheses are obtained through repeatedly extracting Lu from ~4×10^(-4)mol/L of Lu aqueous feed solution with initial pH of 2.40 by 0.01 mol/L extractant at phase ratio A/O of 1:1.

关键词： Heavy rare earth element Dialkylphosphinic acid Extraction Loading capacity Emulsification

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Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de/hydrogenation performance of magnesium hydride

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Rare Metals 2024年第7期43卷 3273-3285页

作者： Meng-chen Song Fu-Ying Wu Yi-Qun Jiang Xiu-zhen Wang Hu Zhao Li-Xin chen Liu-Ting Zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and Technology Max Planck Institute for Iron Research School of Mechanical and Aerospace Engineering Nanyang Technological University State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang University

The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride（MgH2） in sustainable energy ***,FeCoNiCrTi high-entropy alloy（HEA） nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH2to boost the hydrogen storage *** refined HEA exhibited superior catalytic activity on *** contrast to additive-free MgH2,the initial desorption temperature of the constructed MgH2-HEA composite was reduced from 330.0 to 198.5℃ and a remarkable 51% reduction in the dehydrogenation activation energy was ***,the MgH2-HEA composite only required one-twentieth time of that consumed by pure MgH2to absorb 5.0 wt% of H2at 225℃.The synergy between the "hydrogen pumping" effect of Mg2Ni/Mg2NiH4and Mg2Co/Mg2CoH5couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH2contributed to the enhanced de/hydrogenation performance of the MgH2-HEA *** study furnishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.

关键词： Hydrogen storage Magnesium hydride High-entropy alloys Catalysis

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Emergent symmetry in quantum phase transition:From deconfined quantum critical point to gapless quantum spin liquid

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Science Bulletin 2024年第2期69卷 190-196页

作者： wen-Yuan Liu Shou-Shu Gong Wei-Qiang chen zheng-cheng Gu Department of Physics The Chinese University of Hong KongHong KongChina Division of Chemistry and Chemical Engineering California Institute of TechnologyPasadena CA 91125USA School of Physical Sciences Great Bay UniversityDongguan 523000China Great Bay Institute for Advanced Study Dongguan 523000China Department of Physics and Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and TechnologyShenzhen 518055China

The emergence of exotic quantum phenomena in frustrated magnets is rapidly driving the development of quantum many-body physics,raising fundamental questions on the nature of quantum phase *** we unveil the behaviour of emergent symmetry involving two extraordinarily representative phenomena,i.e.,the deconfined quantum critical point(DQCP)and the quantum spin liquid(QSL)*** large-scale tensor network simulations,we study a spatially anisotropic spin-1/2 square-lattice frustrated antiferromagnetic(AFM)model,namely the J1x-J1y-J2 model,which contains anisotropic nearestneighbor couplings J1x,J1y and the next nearest neighbor coupling *** small J1y/J1x,by tuning J2,a direct continuous transition between the AFM and valence bond solid phase is *** growing J1y/J1x,a gapless QSL phase gradually emerges between the AFM and VBS *** observe an emergent O(4)symmetry along the AFM–VBS transition line,which is consistent with the prediction of DQCP *** surprisingly,we find that such an emergent O(4)symmetry holds for the whole QSL–VBS transition line as *** findings reveal the intrinsic relationship between the QSL and DQCP from categorical symmetry point of view,and strongly constrain the quantum field theory description of the QSL *** phase diagram and critical exponents presented in this paper are of direct relevance to future experiments on frustrated magnets and cold atom systems.

关键词： Tensor network Quantum phase transition Emergent symmetry Quantum spin liquid Deconfined quantum critical point Anisotropic

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Study of the blocking mechanism in gravel packing based on CFD-DEM

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Particuology 2024年第7期90卷 164-178页

作者： Fucheng Deng Lei wen Gang Li Baitao Fan Ning Gong Shenghong chen Yangtze University Jingzhou434023China Guangzhou Institute of Energy Conversion Chinese Academy of Sciences510640China CNOOC Research Institute Ltd Beijing100028China Tianjin Branch of CNOOC Ltd Tianjin300459China CNOOC Ener Tech-Drilling&Production Co Tianjin300457China

Gravel packing sand control(GPSC),as the optimization of mechanical sand control technology,is widely used in the deep water completion and sand control of loose sandstone heavy oil reservoirs and highly *** explore the blocking mechanism of GPSC,the influence of its structural parameters on the blocking of GPSC is *** paper establishes a particle element model based on computational fluid dynamics-discrete element method coupling using the discrete element method and establishes a fluid flow model combined with computational fluid dynamics to realize their full coupling *** sand control experiments were carried out using a micro visual sand control simulation device to verify the blocking *** blocking mechanism is analyzed from the microscopic point of view,and then,the influence of sand control structure parameters on the blocking in GPSC design is *** results show the following:(1)the blocking process of GPSC can be divided into three stages:an initial stage,sand accumulation stage,and equilibrium stage.(2)There are two main types of gravel packing *** first type of blocking is blocking on the surface of the gravel *** particles on the surface of gravel layer mainly exist in the form of large particle size blocking gravel pores and sand particles bridging each *** second type of blockage is the blockage inside the gravel *** particles mainly exist in the form of internal mud cakes and adsorption on gravels inside the gravel layer.(3)To ensure the sand control performance of the gravel layer,the gravel layer thickness is designed between 23 and 28 *** displacement or pressure of the on-site packing pump should be increased to ensure that the gravel layer packing solidity ranges between 59%and 62%.In the design of GPSC,it should be ensured that the median particle size of gravel is 5–6 times the median particle size of *** study provides an effective technical reference for the

关键词： CFD-DEM Blocking the process Blocking mechanism Structural parameter

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Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin

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Petroleum Science 2024年第1期21卷 115-124页

作者： wen-Yang Wang Xiong-Qi Pang Ya-Ping Wang Zhang-Xin chen Fu-Jie Jiang Ying chen State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Research Institute of Exploration and Development PetroChina Southwest Oil&Gas Field CompanyChengdu610041SichuanChina Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryT2N 1N4Canada

With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration ***,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum *** it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the ***,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the *** this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained *** depth corresponding to a dry layer ratio of 100%is the *** on this,a quantitative prediction model for the DLOA was finally *** results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep *** critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the *** depth of the DLOA was 9,000 *** study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling.

关键词： Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model

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Construction of electron rich Fe active sites by FeCu alloy anchoring on carbon nitride for photocatalytic nitrogen reduction

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Rare Metals 2024年第4期43卷 1570-1579页

作者： Gang Dong Cong Huang Fei-Yang chen Xue-Qin Liu zhen Li Xiao-Li Su Tao Zeng Yun-Xia chen Yi-Huang chen Yang Wang School of Materials Science and Engineering Jingdezhen Ceramic UniversityJingdezhen333403China Faculty of Materials Science and Chemistry China University of GeosciencesWuhan430074China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China

Given the clean and inexhaustible solar energy from solar light,photocatalytic ammonia synthesis is extremely ***,high electron-hole recombination rates and insufficient active sites severely limited N2 photoreaction ***,we designed and fabricated FeCu alloy nanoparticles anchored on carbon nitride nanosheets with excellent photocatalyt ic ammonia synthesis *** a coupler between Fe and carbon nitride,Cu promotes the separation of photogenerated charge carriers in carbon nitride under solar light irradiation,and renters the semiconductor a forceful electron donor for the Fe active *** accumulated electrons at Fe sites furtherly facilitated the adsorption and activation of the molecular ***,the uniform dispersed FeCu alloy nanoparticles were on carbon nitride nanosheets enhanced the stability of photocataly tic nitrogen reduction reaction,making the artificial photocataly tic ammonia synthesis more sustainable for *** work highlights that a direct electron transfer channel can be used to regulate the photochemical nitrogen fixation network.

关键词： Photocatalytic N_2 fixation Carbon nitride FeCu alloy Active sites Hydrogenation pathway

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Automated machine learning for rainfall-induced landslide hazard mapping in Luhe County of Guangdong Province,China

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China Geology 2024年第2期7卷 315-329页

作者： Tao Li chen-chen Xie Chong Xu wen-wen Qi Yuan-dong Huang Lei Li National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing 100085China Institute of Disaster Prevention Sanhe 065201China School of Emergency Management Science and Engineering University of Chinese Academy of SciencesBeijing 100049China

Landslide hazard mapping is essential for regional landslide hazard *** main objective of this study is to construct a rainfall-induced landslide hazard map of Luhe County,China based on an automated machine learning framework(AutoGluon).A total of 2241 landslides were identified from satellite images before and after the rainfall event,and 10 impact factors including elevation,slope,aspect,normalized difference vegetation index(NDVI),topographic wetness index(TWI),lithology,land cover,distance to roads,distance to rivers,and rainfall were selected as *** WeightedEnsemble model,which is an ensemble of 13 basic machine learning models weighted together,was used to output the landslide hazard assessment *** results indicate that landslides mainly occurred in the central part of the study area,especially in Hetian and *** 102.44 s were spent to train all the models,and the ensemble model WeightedEnsemble has an Area Under the Curve(AUC)value of92.36%in the test *** addition,14.95%of the study area was determined to be at very high hazard,with a landslide density of 12.02 per square *** study serves as a significant reference for the prevention and mitigation of geological hazards and land use planning in Luhe County.

关键词： Landslide hazard Heavy rainfall Harzard mapping Hazard assessment Automated machine learning Shallow landslide Visual interpretation Luhe County Geological hazards survey engineering

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The Bright Single Pulse Emission from PSR B1133+16

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Research in Astronomy and Astrophysics 2024年第4期24卷 253-261页

作者： Jun Tan Zhi-Gang wen zhen Wang Xue-Feng Duan Hong-Guang Wang Na Wang Vishal Gajjar Jian-Ping Yuan Rai Yuen wen-Ming Yan Jian-Ling chen Wei Han Hui Wang cheng-Bing Lyu Ai-Jun Dong Maths and Information Technology School Yuncheng UniversityYuncheng 044000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Space Science Laboratory University of CaliforniaBerkeley 94710USA Department of Physics and Electronic Engineering Yuncheng UniversityYuncheng 044000China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China

We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio *** time resolution data(61μs)were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr.A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse ***,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse *** majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately *** pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-*** updated nulling fraction of 15.35%±0.45% was determined from the energy *** emission of individual pulses follows a log-normal distribution in peak flux density *** is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first *** physical mechanisms are discussed in detail to provide insights into these observations.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR B1133+16) methods:observational methods:data analysis

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A randomized, controlled, multicenter contraceptive efficacy clinical trial of the intravas device, a nonocclusive surgical male sterilization

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Asian Journal of Andrology 2014年第3期16卷 432-436页

作者： wen-Hong Lu Xiao-Wei Liang Yi-Qun Gu Wei-Xiong Wu Li-Wei Bo Tian-Gui zheng zhen-wen chen Key Laboratory of Male Reproductive Health National Health and Family Planning Commission National Research Institute for Family Planning and WHO Collaborating Centre for Research in Human Reproduction Beijing Institute for Family Planning of Guangzhou city Guangzhou Institute for Family Planning of Henan Province Zhengzhou Institute for Family Planning of Putian City Putian China.

Because of unavoidable complications of vasectomy, this study was undertaken to assess the efficacy and safety of male sterilization with a nonobstructive intravas device （IVD） implanted into the vas lumen by a mini-surgical method compared with no-scalpel vasectomy （NSV）. IVDs were categorized into two types： IVD-B has a tail used for fixing to the vas deferens （fixed wing） whereas IVD-A does not. A multicenter prospective randomized controlled clinical trial was conducted in China. The study was comprised of 1459 male volunteers seeking vasectomy who were randomly assigned to the IVD-A （n = 487）, IVD-B （n = 485） or NSV （n = 487） groups and underwent operation. Follow-up included visits at the 3rd-6TM and 12~ postoperative months, The assessments of the subjects involved regular physical examinations （including general and andrological examinations） and semen analysis. The subjects＇ partners also underwent monitoring for pregnancy by monthly interviews regarding menstruation and if necessary, urine tests, There were no significant differences in pregnancy rates （0.65% for IVD-A, 0 for IVD-B and 0.21% for NSV） among the three groups （P 〉 0.05）. The cumulative rates of complications at the 12th postoperative month were zero, 0.9% and 1.7% in the three groups, respectively. In conclusion, IVD male sterilization exhibits a low risk of long-term adverse events and was found to be effective as a male sterilization method, similar to the NSV technique. IVD male sterilization is expected to be a novel contraceptive method.

关键词： complication male sterilization nonobstructive intravas device no-scalpel vasectomy

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Frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university students

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 374-379页

作者： Jie Cai wen-wen Fan Yun-Hui Zhong Cai-Lan wen Xiao-Dan Wei Wan-chen Wei Wan-Yan Xiang Jin-Mao chen Department of Ophthalmology First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Digital and Intelligent Technology Transformation and Application Research Institute of Visual Function Tianjin 300000China Guangxi Medical University Nanning 530021Guangxi Zhuang Autonomous RegionChina

AIM:To investigate the frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university ***:Totally 158 student volunteers underwent routine vision examination in the optometry clinic of Guangxi Medical *** data were used to identify the different types of accommodation and nonstrabismic binocular vision dysfunction and to determine their *** analysis and logistic regression were used to examine the factors associated with these ***:The results showed that 36.71%of the subjects had accommodation and non-strabismic binocular vision issues,with 8.86%being attributed to accommodation dysfunction and 27.85%to binocular *** insufficiency(CI)was the most common abnormality,accounting for 13.29%.Those with these abnormalities experienced higher levels of eyestrain(χ2=69.518,P<0.001).The linear correlations were observed between the difference of binocular spherical equivalent(SE)and the index of horizontal esotropia at a distance(r=0.231,P=0.004)and the asthenopia survey scale(ASS)score(r=0.346,P<0.001).Furthermore,the right eye's SE was inversely correlated with the convergence of positive and negative fusion images at close range(r=-0.321,P<0.001),the convergence of negative fusion images at close range(r=-0.294,P<0.001),the vergence facility(VF;r=-0.234,P=0.003),and the set of negative fusion images at far range(r=-0.237,P=0.003).Logistic regression analysis indicated that gender,age,and the difference in right and binocular SE did not influence the emergence of these ***:Binocular vision abnormalities are more prevalent than accommodation dysfunction,with CI being the most frequent *** binocular refractive disparity leads to more severe eyestrain symptoms.

关键词： optometry clinic non-strabismic binocular vision dysfunction college students convergence insufficiency

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