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Chinese Chemical Letters 2009年第3期20卷 334-338页

作者： li na hu Zhao Gang Ren College of Chemistry and Chemical Engineering China West Nomal University Nanchong 637002 China

This paper described a novel method for the preconcentration of Pb（II） using microcrystalline triphenylmethane loaded with quinolin-8-olate prior to the determination by flame atomic absorption spectrometry. Pb（II） could be enriched by controlling appropriate condition. The preconcentration factor could reach to 200 and the detection limit of Pb（II） was 0.074 μg/L. The recovery was in a range of 93.5-103% with relative standard deviation of 1.0-2.2%. The proposed method had been successfully applied to the determination of trace Pb（U） in various water samples with satisfactory result.

关键词： Microcrystalline triphenylmethane Quinolin-8-olate Separation Preconcentration and determination

Pair production in inhomogeneous electric fields with phase modulation

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Communications in Theoretical Physics 2023年第2期75卷 60-72页

作者： li-na hu Orkash Amat lie-Juan li Melike Mohamedsedik B S Xie Key Laboratory of Beam Technology of the Ministry of Education and College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Electron-positron pair production in spatial inhomogeneous electric fields with sinusoidal phase modulation is studied within the Dirac-Heisenberg-Wigner *** focus is on discussing the effects of the modulation parameters on the momentum spectrum and the reduced particle number at various spatial *** the momentum spectrum,the interference effect becomes more and more remarkable with the increase of modulated amplitude or frequency,while the symmetry is severely destroyed with modulated *** the reduced particle number,it is greatly enhanced by about a few times and evenly one order of magnitude when modulation parameters are ***,the effect of spatial scales on the reduced particle number is carefully examined,and it is found that it increases rapidly at small spatial scales,while it tends to be a constant at large spatial *** also obtain the optimal pair production that can be achieved through different *** results can provide a possibility for realizing the optimal pair production by combining the advantages of field spatial inhomogeneity with different choices of phase modulation.

关键词： inhomogeneous phase momentum

Assisted Hatching in Couples with Advanced Maternal Age： A Systematic Review and Meta-analysis

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Current Medical Science 2018年第3期38卷 552-557页

作者： Fan HE Chan-yu ZHANG li-si WANG Sang-lin li li-na hu The Center for Reproductive Medicine Obstetrics and Gynecology Department the Second Affiliated Hospital ofChongqing Medical University Chongqing 400010 China

This systematic review aimed to evaluate the efficacy and safety of assisted hatching （AH） performed in couples with advanced maternal age. We searched for randomized controlled trials （RCTs） in electronic databases, including MEDliNE, EMBASE and CENTRAL （from inception to January 2018）; in addition, we hand-searched the reference lists of included studies and similar reviews. We included RCTs comparing AH versus no treatment （control）. The meta-analysis was performed by RevMan 5.3 software. The search retrieved 943 records and 8 RCTs were included, comprising 870 cycles （n=440 for AH, and n=430 for control）. There was no significant difference in the rates of live birth （RR 0.88, 95% CI 0.65 to 1.18, 3 RCTs, n-427,I^2=0%）, clinical pregnancy （RR 1.00, 95% CI 0.83 to 1.19, 8 RCTs, n=870, I^2=22%）, implantation （RR 1.07, 95% CI 0.83 to 1.39, 4 RCTs, n=1359, I^2=0%）, miscarriage （RR 1.13, 95% CI 0.66 to 1.94, 2 RCTs, n=116, I^2=0%） and multiple pregnancy （RR 0.89, 95% CI 0.31 to 2.52, 1 RCT, n=97,I^2=not applicable） between the treatment group and control group. No reasonable conclusions could be drawn regarding reproductive outcomes after AH in patients with advanced maternal age due to the small sample pooled in meta-analyses. Studies of high methodological quality and with adequate power are necessary to further investigate the value of AH in assisted conception of those patients.

关键词： assisted hatching advanced maternal age in vitro fertilization frozen-thawed embryo transfer

Microstructural Features and Mechanical Behaviors of Al_(0.5)Cr_(0.8)CoFeNi_(2.5)V_(0.2) High-Entropy Alloys Fabricated by Selective Laser Melting Technique

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Acta Metallurgica Sinica(English Letters) 2022年第10期35卷 1591-1606页

作者： Yao Yan Wei-Dong Song Ke-Feng li Kang Zhao Tong-Tong Sun Kai-Kai Song Jian-Hong Gong li-na hu Shenzhen Research Institute of Shandong University Shenzhen518057China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Guangdong Institute of Materials and Processing Guangdong Academy of SciencesGuangdong UniversityGuangzhou510650China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai264209China Key Laboratory for liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan250061China

In this work,high strength and ductile Al_(0.5)Cr_(0.8)CoFeNi_(2.5)V_(0.2) high-entropy alloys(HEAs)were fabricated by the selective laser melting(SLM)*** orthogonal experiments,it was verified that a wide SLM processing parameter window can be used to produce crack-free samples for the investigated *** the printed HEA samples exhibit good densification higher than 98.3%.It was found that obvious epitaxial growth leads to the formation of the cylindrical and equiaxed ordered face-centered cubic(FCC)crystals,displaying the characteristics of sub-cylindrical and sub-cellular *** low-angle grain boundaries(LAGBs)prefer appearing around subgrain structures,while the high-angle grain boundaries(HAGBs)tend to form around coarse *** HEA samples with high and low apparent densities were selected to observe their mechanical properties,which exhibit Vickers hardness higher than 263 HV and do not fail during *** increasing densification,the strength gradually *** to the engineering stress–strain curves during compression,the yield strength is higher than 530 MPa,while the strength near 40%engineering strain is larger than 1840 *** deformation,a large density of dislocations becomes popular within subgrain structures together with the pre-existing dislocations from rapid solidification,leading to the formation of planar and cross slip *** coarse cylindrical crystals,some deformation twins are also induced together with the appearance of a distinct copper-type texture during *** a result,the as-printed samples display better mechanical properties than the as-cast *** present studies provide a very good HEA candidate for the SLM process,but more work should be conducted to achieve excellent comprehensive properties.

关键词： High-entropy alloys Selective laser melting Mechanical properties Microstructures

Enhanced mechanical performance of gradient-structured CoCrFeMnNi high-entropy alloys induced by industrial shot-blasting

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Rare Metals 2023年第3期42卷 982-993页

作者： Ming-Zhi Zhang Kun Zhang Kai-Kai Song Xiao-Yu Zou Wei-Dong Song Ke-Feng li li-na hu Ze-Qun Zhang Jürgen Eckert Shenzhen Research Institute of Shandong University Shenzhen 518057China CAS Key Laboratory of Microgravity(national Microgravity Laboratory) Institute of MechanicsChinese Academy of SciencesBeijing100190China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai 264209China Guangdong Institute of Materials and Processing Guangdong Academy of SciencesGuangzhou 510650China Key Laboratory for liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China Erich Schmid Institute of Materials Science Austrian Academy of SciencesLeoben 8700Austria Department of Materials Science Montanuniversitat LeobenLeoben 8700Austria

In this study,CoCrFeMnNi high-entropy alloys(HEAs)with a surface gradient nanostructure were produced using industrial shot blasting,which improved their mechanical properties compared to the untreated *** severely plastically deformed(SPD)surface layer had a multi-scale hierarchical structure with a high density of stacking faults,deformation nanotwins,and amorphous *** depth of the SPD layer steadily increased as the shot-blasting time *** differences in the microhardness and tensile strength before and after shotblasting demonstrated the significant effect of the SPD layer on the mechanical *** microhardness of the homogenized HEA was~5 *** comparison,the maximum microhardness of the specimens after 20 min of shot blasting was~8.0 GPa at the *** yield strength also improved by 178%,and a large ductility of~36%was *** nanograin boundary,stacking fault,and twin strengthening within the gradientnanostructured surface layer caused the strength to *** tensile deformation,strain concentration began at the surface of the specimen and gradually spread to the ***,the gradient-nanostructured surface layer with improved strain hardening can prevent early necking and ensure steady plastic deformation so that high toughness is achieved.

关键词： High-entropy alloy Shot blasting Gradient structure Mechanical property Deformation mechanism

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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Science China Chemistry 2009年第8期52卷 1097-1103页

作者： li XiangJun,ZHENG na,hu ZhongBo & YUAN ZhuoBin College of Chemistry and Chemical Engineering,Graduate University of Chinese Academy of Sciences,Beijing 100049,China 1. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Study of Electron Transfer Reactions Between a Water/1,2-Dichloroethane Interface by Scanning Electrochemical Microscopy

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Chinese Chemical Letters 2004年第12期15卷 1461-1464页

作者： Xiao Quan LU li na hu Xiao Qiang WANG Jing CHEN College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070 College of Chemistry & Chemical Engineering Northwest Normal University

Electron transfer (ET) from ascorbic acid (AA) in aqueous to ferrocene (Fc) in1,2-dichloroethane (DCE) was probed by the scanning electrochemical microscopy (SECM). Therate constants were extracted from the dependence of the steady-state current at ultramicro-electrode(UME, tip) on the distance between the tip and the phase boundary by comparison to theoreticalworking cures.

关键词： SECM electron transfer ascorbic acid.

Comparison of Mitoxantrone in Combination with Intermediate-dose Cytarabine versus High-dose Cytarabine as Consolidation Therapies for Young Non-APL Acute Myeloid Leukemia Patients with Favorable and Intermediate Cytogenetics

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Journal of huazhong University of Science and Technology(Medical Sciences) 2018年第1期38卷 51-57页

作者： Ji-hao ZHOU Hai-qing liN Qi SHEN li-na hu Guo-qiang li Xiong-fei SUN Xin-you ZHANG Department of Hematology The Second Clinical Medical College of Jinan University （Shenzhen People＇s Hospital） Jinan University Shenzhen 518020 China

In this study,we compared the efficacy of mitoxantrone in combination with intermediate-dose cytarabine（HAM） with that of high-dose cytarabine alone（Hi DAC） as consolidation regimens in non-acute promyelocytic leukemia（APL） acute myeloid leukemia patients with favorable and intermediate cytogenetics.A total of 62 patients from Shenzhen People＇s Hospital were enrolled in this *** patients enrolled received standard induction chemotherapy and achieved the first complete remission（CR1）.In these patients,24 received Hi DAC and 38 received HAM as *** median relapse free survival（RFS） and overall survival（OS） were similar between these two consolidation *** in subgroup analysis according to risk stratification,the combination regimen conferred no benefit in longterm outcome in patients with favorable or intermediate ***,in patients receiving HAM regimen,the lowest neutrophil count was lower,neutropenic period longer,neutropenic fever rate higher,and more platelet transfusion support was *** group also tended to have higher rate of sepsis than Hi DAC *** to our results,we suggest that combination treatment with mitoxantrone and intermediate-dose cytarabine has limited value as compared to Hi DAC,even in young non-APL AML patients with favorable and intermediate cytogenetics.

关键词： cytarabine mitoxantrone consolidation acute myeloid leukemia cytogenetics

Property evolution and service life prediction of novel metallic materials for future lunar bases

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Rare Metals 2024年第10期43卷 5318-5331页

作者： Sen-Kuan Meng Rui-Song Zhu Hong-liang Zheng Tong Gao Shi-Hao Jiang Wen-Hao Wang Shu-Hao Zhang Zi-Yuan Zhao Xuan Ge Wei-Min Wang li-na hu Zheng Wang Key Laboratory for liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China Department of Chemistry and Bioscience Aalborg University9220AalborgDenmark

While lunar bases have been a focus of development in recent years,the complex and extreme environment of the lunar surface remains a considerable challenge for lunar *** those on Earth,lunar day and night temperature variations cause the properties of materials,especially metallic materials,to evolve in completely different *** this study,we investigated the property evolution of nine typical highperformance metallic materials using laboratory simulations of the extremely long-period lunar temperature *** lunation treatment improves the properties of all metallic materials,the microscopic mechanisms vary for amorphous and crystalline alloys with different *** treatment reduces both the loosely packed regions and heterogeneity in amorphous alloys while causing significant phase changes in crystalline ***,a conservative prediction of the service life of metallic materials on lunar bases is provided based on analyzing microplastic events,followed by the practical material selection recommendations in various lunar application scenarios.

关键词： Metallic glass Property evolution Lunar exploration Metallic material

Arsenic trioxide in treatment of de novo acute basophilic leukemia

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Chinese Medical Journal 2013年第3期126卷 593-594页

作者： ZHAO Yan-hong KONG De-sheng HAN li-na hu Long-hu ZHANG Zhuo liU Jing-jing liU Shuang-xia QIN Fan ZHOU Jin Department of Hematology First Affiliated Hospital Harbin Medical University Harbin Heilongjiang 150001 China

Acute basophilic leukemia （ABL） is a rare subtype of .acute myeloid leukemia （AML）, accounting for 4%-5% of AML and less than 2% of all hematopoietic malignancies. It is usually characterized by a very rapid clinical course, symptoms of hyperhistaminemia, peptic ulceration, gastrointestinal cerebrovascular bleeding and resistance to therapy.^1 However, the clinical outcome of ABL remains disapp2ointing. Most patients died within 1 year after diagnosis.

关键词： acute basophilic leukemia arsenic trioxide