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Technology development for rare earth cleaner hydrometallurgy in China

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Rare Metals 2015年第4期34卷 215-222页

作者： Xiao-Wei Huang Zhi-Qi Long Liang-Shi Wang Zong-Yu Feng National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd.

China is the global leader in rare earth （RE） production using hydrometallurgical processes. Advantageous extraction techniques of rare earths from Baotou mixed rare earth minerals, bastnaesite, and ion-adsorption clays of rare earth deposits have been developed in China. The separation and purification technologies have also achieved rapid development. The industrial application processes for rare earth hydrometallurgy were summarized in the present paper. With the large demands and rapid development of rare earths, the issues of resources and environment are more prominent. This review gives an overview of the main processes that were developed in the past toward greener hydrometallurgy of rare earths in China. Based on the development of the rare earth industry, comprehensive utilization and cleaner production should still be focused on in the future, to support the sustainable development.

关键词： Rare earths Cleaner production Separation and purification Hydrometallurgy

Physical and numerical investigation on fluid flow and inclusion removal behavior in a single-strand tundish

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Journal of Iron and Steel Research(International) 2023年第6期30卷 1182-1198页

作者： qi Quan zhi-xiao Zhang Tian-peng Qu Xiang-long Li Jun Tian De-yong Wang School of Iron and Steel Soochow UniversitySuzhou 215137JiangsuChina

Aiming at the problem that the existence of inclusions in the tundish continuous casting process can easily lead to quality defects of the slab,the stainless steel continuous casting tundish was taken as the research object.The effects of flow control device,inclusion density and inclusion size on the mixing characteristics of molten steel and inclusion behavior in tundish were studied.The results showed that compared with the tundish without flow control device,the average residence time of molten steel was prolonged by about 49 s,the dead zone volume fraction was reduced by 8.93%,and the piston fluid integral rate was increased by 12.68%.In the turbulence inhibitor(TI)tundish with weir-dam combination,the removal rate of inclusions with a density of 2700 kg m^(-3) and a particle size of 5 lm is 63.32%,while the removal rate of large inclusions with a density of 150μm could reach 89.04%.When the inclusion particle size was 10-50μm and the density was 2700-4500 kg m^(-3),the effect of inclusion density on inclusion removal rate was small.At the same time,when weir-dam combination TI tundish was set,the inclusions were mainly limited to the slag-metal interface of the first and second chambers of the tundish.The removal rate of inclusions in the first chamber was generally improved,with 10μm inclusions accounting for 47.67% and 150μm inclusions accounting for 60.69%.Furthermore,it has the best effect on the removal of small-size inclusions,especially those less than 70μm.

关键词： Non-metallic inclusion Flow control device Residence time distribution curve Removal behavior Discrete particle model

Effects of the momentum dependence of nuclear symmetry potential on pion observables in Sn+Sn collisions at 270 MeV/nucleon

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Nuclear Science and Techniques 2022年第12期33卷 147-158页

作者： Gao‑Feng Wei Xin Huang qi‑Jun zhi Ai‑Jun Dong Chang‑Gen Peng Zheng‑Wen long School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Public Big Data Guizhou UniversityGuiyang 550025China College of Physics Guizhou UniversityGuiyang 550025China

Within a transport model,we investigated the effects of the momentum dependence of the nuclear symmetry potential on the pion observables in central Sn+Sn collisions at 270 MeV/nucleon.To this end,the quantity U^(∞)_(sym)(ρ_(0))(i.e.,the value of the nuclear symmetry potential at the saturation densityρ_(0) and infinitely large nucleon momentum)was used to characterize the momentum dependence of the nuclear symmetry potential.With a certain L(i.e.,the slope of the nuclear symmetry energy at(ρ_(0))),the characteristic parameter U^(∞)_(sym)(ρ_(0))of the symmetry potential significantly affects the production of−and+and their pion ratios.Moreover,by comparing the charged pion yields,pion ratios,and spectral pion ratios of the theoretical simulations for the reactions ^(108) Sn+^(112) Sn and ^(132)Sn+^(124)Sn with the corresponding data in the SRIT experiments,we found that our results favor a constraint on U^(∞)_(sym)(ρ_(0))(i.e.,−160_(−9)^(+18) MeV),and L is also suggested within a range of 62.7 MeV

关键词： Nuclear symmetry potential Momentum dependence Symmetry energy

Foam/Film Alternating Multilayer Structure with High Toughness and Low Thermal Conductivity Prepared via Microlayer Coextrusion

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Chinese Journal of Polymer Science 2021年第5期39卷 566-572,I0006页

作者： qi LUO Hong-Ting PU zhi-Hua Zhang Xiong Zhang Cheng-long Yu Department of Polymeric Materials School of Materials Science&EngineeringTongji UniversityShanghai 201804China Key Laboratory of Advanced Civil Engineering Materials(Ministry of Education) Tongji UniversityShanghai 201804China School of Physics Science and Engineering&Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology Tongji UniversityShanghai 200092China

Multilayer membranes prepared via microlayer coextrusion have attracted wide attention due to their unique properties and broad applications.In present study,the foam/film alternating multilayer sheets based on ethylene-vinyl acetate copolymer(EVA)and high-density polyethylene are successfully prepared via microlayer coextrusion.The cells in the sheets are single-cell-array along the foamed EVA layers with uniform cell size.In addition,the effects of layer number and foam relative thickness on morphology,mechanical properties,damping and heat insulation properties are investigated.The cell size decreases significantly with increasing layer number due to the enhanced confine effects.The tensile strength,elongation at break,and heat insulation also increase significantly.However,the mechanical damping properties change little in the observed frequency.Meanwhile,with higher relative thickness of EVA foam,the sheets have lower tensile strength and lower thermal conductivity,while the damping properties are enhanced in a specific frequency scope.The elongation at break of the optimized sample comes to 800%and the thermal conductivity decreases to 61 mW·m^(-1)·K^(-1),which shows high toughness and low thermal conductivity,indicating a possible method for preparing materials with high toughness and heat-insulating properties.

关键词： Multilayer Foam Coextrusion Toughness Thermal conductivity

Walking Cations: Transition-Metal Free Benzyl Cation-Triggered sp^(2) C—H Phosphorylation and Etherification

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Chinese Journal of Chemistry 2022年第24期40卷 2933-2938页

作者： Kuan Liu Bin Song qi Dang long Liu Jie Tang Tianzeng Huang Chunya Li zhi Tang Tieqiao Chen Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources Hainan Provincial Key Lab of Fine ChemHainan Provincial Fine Chemical Engineering Research CenterHainan UniversityHaikouHainan570228 China

A novel benzyl cation-triggered site-selective sp^(2) C—H phosphorylation and etherification was developed. This reaction was conducted under the transition metal-free conditions through cation migration via dearomatization. Under the reaction conditions, the derivatives of naphthalenes, benzofurans and benzo[b]thiophenes all can be transformed into the corresponding products in good to excellent yields. It provides a method to construct sp^(2) C—P and sp^(2) C—O bonds as well as a new strategy for benzylic activation-triggered sp^(2) C—H functionalization.

关键词： Transition metal-free Cation migration Site-selectivity Phosphorylation Etherification

A Bilayer High-Temperature Dielectric Film with Superior Breakdown Strength and Energy Storage Density

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Nano-Micro Letters 2023年第9期15卷 479-491页

作者： Jiang-Bo Ping qi-Kun Feng Yong-Xin Zhang Xin-Jie Wang Lei Huang Shao-long Zhong zhi-Min Dang State Key Laboratory of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China

The further electrification of various fields in production and daily life makes it a topic worthy of exploration to improve the performance of capacitors for a long time,including thin-film capacitors.The discharge energy density of thin-film capacitors that serves as one of the important types directly depends on electric field strength and the dielectric constant of the insulation material.However,it has long been a great challenge to improve the breakdown strength and dielectric constant simultaneously.Considering that boron nitride nanosheets(BNNS)possess superior insulation and thermal conductivity owing to wide band gap and 2-dimensional structure,a bilayer polymer film is prepared via coating BNNS by solution casting on surface of polyethylene terephthalate(PET)films.By revealing the bandgap and insulating behavior with UV absorption spectrum,leakage current,and finite element calculation,it is manifested that nanocoating contributes to enhance the bandgap of polymer films,thereby suppressing the charge injection by redirecting their transport from electrodes.Worthy to note that an ultrahigh breakdown field strength(~736 MV m^(−1)),an excellent discharge energy density(~8.77 J cm^(−3))and a prominent charge-discharge efficiency(~96.51%)are achieved concurrently,which is ascribed to the contribution of BNNS ultrathin layer.In addition,the modified PET films also have superior comprehensive performance at high temperatures(~120°C).The materials and methods here selected are easily accessible and facile,which are suitable for large-scale roll-to-roll process production,and are of certain significance to explore the methods about film modification suitable for commercial promotion.

关键词： Film capacitor Dielectric property Boron nitride nanosheets Surface coating Energy storage characteristics

Will male semen quality improve with environmental quality?

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Asian Journal of Andrology 2023年第2期25卷 252-258页

作者： Xu-Chao Dai Meng-qi Zhang Gang Chen Kun Mei Yan-long Liu Hong Huang zhi-Gang Wu School of Public Health and Management Wenzhou Medical UniversityWenzhou 325035China School of Geography Science and Geomatics Engineering Suzhou University of Science and TechnologySuzhou 215009China School of Mental Health Wenzhou Medical UniversityWenzhou 325035China Research Center for Healthy China Wenzhou Medical UniversityWenzhou 325035China Zhejiang Provincial Key Laboratory of Watershed Sciences and Health Wenzhou 325035China Department of Urology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Reproductive Health Research Center Health Assessment Center of Wenzhou Medical UniversityWenzhou 325000China

Wenzhou has improved its environmental quality because of comprehensive environmental remediation;nevertheless,the semen quality of infertile males remains unclear.This study determined whether better environmental quality improved semen quality in this region.We recorded semen quality data from 22962 infertile males from January 2014 to November 2019 at the Center for Reproductive Health of The First Affiliated Hospital of Wenzhou Medical University(Wenzhou,China).Patients were predominantly 30–35 years old(33.1%)and workers(82.0%),with high school education or lower(77.6%);more than a half of the patients(52.6%)were Wenzhou household registration;and most patients(77.5%)had abnormal semen quality.Patients who were older than 40 years and workers,and those with Wenzhou household registration,had significantly worse semen quality(all P<0.05).From 2014 to 2019,progressive sperm motility,total sperm motility,and semen volume showed increasing linear trends in all patients(P=0.021,0.030,and 0.005,respectively),yet normal sperm morphology showed a linearly decreasing trend(P=0.046).Sensitivity analyses for subgroups yielded similar results.In conclusion,the improvement of environmental quality and better function of the accessory glands are associated with progressive sperm motility,total sperm motility,and semen volume.Normal sperm morphology is influenced by occupational exposures and personal lifestyle and does not improve with environmental quality.

关键词： environmental quality male infertility semen quality time trend

Sexual,physical and overall adverse effects in patients treated with 5a-reductase inhibitors:a systematic review and meta-analysis

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Asian Journal of Andrology 2022年第4期24卷 390-397页

作者： Jun-Jie Zhang Xiao Shi Ting Wu Meng-Da Zhang Jin Tang Guang-Ming Yin zhi long Le-Ye He Lin qi long Wang Department of Urology The Third Xiangya HospitalCentral South UniversityChangsha 410008China Department of Urology Xiangya HospitalCentral South UniversityChangsha 410013China Department of Gastroenterology The Third Xiangya HospitalCentral South UniversityChangsha 410013China Department of Cardiovascular Medicine The Third Xiangya HospitalCentral South UniversityChangsha 410013China

Postfinasteride syndrome(PFS)is a term coined to characterize a constellation of reported undesirable sexual,physical,and neuropsychiatric side effects.In the present study,we conducted the meta-analysis to demonstrate whether the use of 5α-reductase inhibitors(5ARIs)increases the risk of PFS-like adverse effects.A search of studies published until May 10,2020,was performed using PubMed,EMBASE,and the Cochrane Library.We included randomized controlled trials with at least one comparison between male patients receiving 5ARIs versus placebo for the treatment of benign prostatic hyperplasia(BPH)or androgenetic alopecia(AGA),and identified 34 studies from 28 articles that met our eligibility criteria.In the random-effects model,the overall use of 5ARIs exhibited a 1.87-fold risk of PFS-like adverse effects during the trial(95%confidence interval[CI]:1.64-2.14).Regarding specific types of adverse effects,the use of 5ARIs had a 1.89-fold risk of sexual adverse effects(95%CI:1.74-2.05)and was associated with an increased risk of physical adverse effects(relative risk[RR]:1.31,95%CI:0.80-2.15),albeit without statistical significance.This meta-analysis helped to better define the adverse effects caused by 5ARIs.We concluded that the overall use of 5ARIs significantly increased the risk of PFS-like adverse effects in men with AGA or BPH during treatment.Enhanced awareness of and education on the PFS-like adverse effects are necessary for clinicians.

关键词： 5α-reductase inhibitors adverse effects androgenetic alopecia benign prostatic hyperplasia postfinasteride syndrome

Immunohistochemical analysis of PD-L1 and tumor-infiltrating immune cells expression in the tumor microenvironment of primary signet ring cell carcinoma of the prostate

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Asian Journal of Andrology 2022年第5期24卷 525-532页

作者： qi-Liang Teng Xin-Rui Yang Shuang Wen zhi-Hong Dai Hong-long Wang Tian-qing Liu Liang Wang Bo Fan zhi-Yu Liu Department of Urology Second Affiliated Hospital of Dalian Medical UniversityDalian 116023China Department of Clinical Imaging Second Affiliated Hospital of Dalian Medical UniversityDalian 116023China Department of Pathology Dalian Friendship HospitalDalian 116001China

Primary signet ring cell carcinoma(SRCC)of the prostate is a rare neoplasm.However,its potential tumorigenic mechanism,clinicopathological features,and prognostic outcome have not been systematically described.To determine the pathogenic mechanism,we detected distributions of programmed cell death-ligand 1(PD-L1),programmed death 1(PD-1),and cellular components in the tumor microenvironment,including tumor-infiltrating lymphocytes(CD4 and CD8),tumor-associated macrophages(TAMs;CD163 and CD68),and tumor-associated fibroblasts(vimentin and alpha-smooth muscle actin[α-SMA]),in tumor tissues from four patients with primary prostatic SRCC compared with corresponding adjacent tissues and tumor tissues from 30 patients with prostate adenocarcinoma(PCa)by immunohistochemical staining.We found higher expression of PD-L1,CD163,and CD68 in primary SRCC specimens than that in both corresponding adjacent nontumor specimens and PCa specimens with different Gleason scores,indicating that TAMs may participate in the malignant biological behavior of primary SRCC of the prostate.For further analysis,we searched electronic journal databases and Surveillance,Epidemiology,and End Results(SEER)to identify 200 eligible patients including our four cases.According to Kaplan–Meier survival curve analysis,patientslonger overall survival(OS).Moreover,Cox multivariate analysis indicated that race(hazard ratio[HR]=1.422),surgical approach(HR=1.654),and Gleason score(HR=2.162)were independent prognostic factors for OS.Therefore,primary SRCC of the prostate represents a distinct and aggressive subtype of prostate cancer associated with a higher distribution of PD-L1 and TAMs,which warrants further clinical investigation.

关键词： clinical features immunohistochemistry infiltrating immune cells primary signet ring cell carcinoma of the prostate tumor microenvironment