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The Selberg-Delange method in short intervals with some applications

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Science China Mathematics 2019年第3期62卷 447-468页

作者： zhen Cui Guangshi Lü jie Wu Department of Mathematics Shanghai Jiao Tong University School of Mathematics Shandong University School of Mathematics and Statistics Yangtze Normal University InstitutElie Cartan de Lorraine Université de Lorraine

In this paper, we establish a quite general mean value result of arithmetic functions over short intervals with the Selberg-Delange method and give some applications. In particular, we generalize Selberg's result on the distribution of integers with a given number of prime factors and Deshouillers-Dress-Tenenbaum's arcsin law on divisors to the short interval case.

关键词： asymptotic results on arithmetic functions Selberg-Delange method arithmetic functions distribution of integers

Impacts of channel morphology on residues and ecological risks of polychlorinated biphenyls in water and sediment in Chahe River

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Water Science and Engineering 2016年第4期9卷 300-311页

作者： zhen-hua Zhao jie Sun Xiao-kun Fang li-ling Xia Javid Hussain Department of Plant Soil and Microbial Sciences Michigan State University East Lansing MI 48824 USA Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education Hohai University Nanjing 210098 China College of Environment Hohai University Nanjing 210098 China Nanjing Institute of Industry Technology Nanjing 210016 China

The impacts of channel morphology on the residues and ecological risks of 14 polychlorinated biphenyl(PCB) congeners in water and sediment were investigated in summer(July) and autumn(September) in the Chahe River,in Nanjing,*** residual concentrations of trichlorobiphenyls(tri-CBs,PCB 18) and tetra-CBs(PCB 52) in water were significantly higher than those of penta-CBs to deca-CBs,and the average residual concentration of ∑PCBs(sum of 14 PCB congeners) in summer was about six times higher than in ***,the residues in sediment did not change *** analysis(RDA) indicated that channel morphology and the corresponding environmental indices had significant impacts on PCB residues and their composition profiles in water and *** overflow weir and lake-type watercourse may remarkably reduce the residual concentration and ecological risks of PCBs in *** highest reduction percentages of the residual concentration and ecological risks of ∑PCBs induced by an overflow weir were 78%and 67%,respectively,and those induced by a lake-type watercourse were 36%and 70%,*** watercourses with different channel morphologies were ranked by residual ∑PCBs concentrations in the following descending order:the natural ecological watercourse,vertical concrete watercourse,and vegetation-type riprap ***,they were ranked by residual ∑PCBs concentrations in sediment in the following descending order:the vertical concrete watercourse,vegetation-type riprap watercourse,and natural ecological watercourse.

关键词： Channel morphology RDA Ecological risk Toxic equivalent concentration

Room-temperature ionic conductivity of Ba,Y,Al co-doped li_(7)La_(3)Zr_(2)O_(12)solid electrolyte after sintering

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Rare Metals 2021年第8期40卷 2301-2306页

作者： Xiao-zhen liu Lei Ding Yu-Ze liu li-Ping Xiong jie Chen Xiao-Long Luo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai201418China College of Economic and Management Beijing Forestry UniversityBeijing100083China Regenia AB Stockholm10691Sweden

The Ba,Y and A1 co-doped li_(7)La_(3)Zr_(2)O_(12)(LLZO)was prepared by the solid-state reaction *** of sintering on the crystallographic structure,morphology,total conductivity,relative density and contractibility rate of the prepared solid electrolyte was studied,*** sintered samples were characterized by X-ray diffractometer(XRD),scanning electron microscopy(SEM),electrochemical impedance spectra(EIS)and inductively coupled plasma atomic emission spectrometry(ICP-AES)techniques,*** cubic garnet phase Ba,Y and Al co-doped LLZO is obtained,and the room-temperature total conductivity of the Ba,Y and Al co-doped LLZO solid electrolyte is improved significantly by eliminating the grain boundary resistances and improving the densifications with controlling sintering temperature(T)and time(t),*** at 1160-1190℃for 12 h and at 1190℃for6-15 h,respectively,the Ba,Y and Al co-doped LLZO solid electrolytes are cubic garnet *** at1180-1190℃for 12 h and at 1190℃for 12-18 h,respectively,SEM images of the cross section of the Ba,Y and Al co-doped LLZO solid electrolytes exhibit the distinctively flattened morphology without any noticeable grain *** total conductivity,relative density and contractibility rate of li_(6.52)La_(2.98)-Ba_(0.02)Zr_(1.9)Y_(0.1)Al_(0.2)O_(12)solid electrolyte are 2.96×10^(-4) S·cm^(-1),94.19%and 18.61%,respectively.

关键词： Solid electrolyte Ionic conductivity Sintering li_(7)La_(3)Zr_(2)O_(12) Garnet

Finite Groups with Some Pronormal Subgroups

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Acta Mathematica Sinica,English Series 2011年第4期27卷 715-724页

作者： zhen Cai SHEN Wu jie SHI School of Mathematical Sciences Suzhou University Suzhou 215006 P. R. China School of Mathematics and Statistics Chongqing University of Arts and Sciences Chongqing 402160 P. R. China

A subgroup H of finite group G is called pronormal in G if for every element x of G, H is conjugate to Hx in （H, Hx）. A finite group G is called PRN-group if every cyclic subgroup of G of prime order or order 4 is pronormal in G. In this paper, we find all PRN-groups and classify minimal non-PRN-groups （non-PRN-group all of whose proper subgroups are PRN-groups）. At the end of the paper, we also classify the finite group G, all of whose second maximal subgroups are PRN-groups.

关键词： Pronormal subgroups PRN-groups minimal non-PRN-groups PN-groups minimalsubgroups p-nilpotent groups

On-demand synthesis of high-quality,blue-light-active ZnSe colloidal quantum wires

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National Science Review 2022年第10期9卷 137-146页

作者： Yi li Chong Zhang jie Tian liang Wu Guo-Qiang liu Hui-Hui li Yu-Zhuo Zhang zhen-Chao Shao zhen He Shu-Hong Yu Department of Chemistry Institute of Biomimetic Materials and Chemistry Anhui Engineering Laboratory of Biomimetic Materials Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of China Engineering and Materials Science Experiment Center University of Science and Technology of China

Beyond the state-of-the-art Cd-containing quantum wires(QWs),heavy-metal-free semiconductor QWs,such as ZnSe,are of great interest for next-generation environmental-benign ***,simultaneous,on-demand manipulation of their radial and axial sizes—that allows strong quantum confinement in the blue-light region—has so far been *** we present a two-step catalyzed growth strategy that enables independent,high-precision and wide-range controls over the diameter and length of ZnSe *** find that a new epitaxial orientation between the cubic-phase Ag2Se solid catalyst and wurtzite ZnSe QWs kinetically favors the formation of defect-free ultrathin *** to their high uniformity,the resulting blue-light-active,phase-pure ZnSe QWs exhibit well-defined excitonic absorption with the 1Se-1Shtransition linewidth as narrow as sub-13 *** the transient absorption spectroscopy,we further show that surface electron traps in these ZnSe QWs can be eliminated by thiol passivation,which results in long-lived charge carriers and high-efficiency solar-to-hydrogen conversion.

关键词： zinc selenide colloidal synthesis quantum wires heavy-metal-free solar conversion

A review of the risk factors associated with juvenile-onset recurrent respiratory papillomatosis:genetic,immune and clinical aspects

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World Journal of Pediatrics 2022年第2期18卷 75-82页

作者： Shi-Lan li Wei Wang Jing Zhao Feng-zhen Zhang jie Zhang Xin Ni Department of Otorhinolaryngology Head and Neck Surgery Beijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 10045China Beijing Key Laboratory for Pediatric Diseases of Otolaryngology Head and Neck SurgeryBeijing Pediatric Research InstituteBeijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 10045China Laboratory of Tumor Immunology.Beijing Pediatric Research Institute Beijing Children's HospitalCapital Medical University.National Center for Children's HealthBeijing 10045China

Background Juvenile-onset recurrent respiratory papillomatosis(JoRRP)is one of the most common benign lesions of hyperplastic respiratory epithelial tissue in children and is predominantly caused by human papillomaviruses(HPVs)6 and *** clinical course of the disease is variable,and some patients even develop a *** purpose of this review was to summarize the related factors affecting the disease course in patients with *** sources We used databases,including PubMed and Google Scholar,to search for publications on factors associated with the genetic,immune,and clinical aspects of *** most relevant articles to the scope of this review were chosen for *** Mother-to-child transmission is the most important mode of disease transmission;other factors,such as immune condition or genetic susceptibility,may be important determinants of JoRRP ***,the presence of DRBI*0301 and HFV 6/11 E6/E7 is associated with a more severe ***,patients have an enhanced T helper 2-like *** addition,regulatory T cells are enriched in tumors and may become one of the effective prognostic *** clinical characteristics,patients infected with HPV-11 have more aggressive ***,compared with HPV type,age at first onset is a more important factor related to the aggressiveness of ***,socioeconomic status may also affect the *** Genetic,immune,and some clinical factors have been noted to play an important role in the course of *** definite influencing factors will be an important direction of research in the future.

关键词： Epidemics Genetic Human papillomavirus infection Immune Recurrent respiratory papillomatosis Risk factors

FeNiS_(2)/reduced graphene oxide electrocatalysis with reconstruction to generate FeNi oxo/hydroxide as a highly-efficient water oxidation electrocatalyst

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Rare Metals 2022年第12期41卷 4127-4137页

作者： Xiao-zhen Ren Xue-Hui li Yu-jie Peng Guan-Zhi Wang jie Yin Xing-Chuan Zhao Wei Wang Xiao-Bai Wang School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252000China School of Metallurgy and Chemistry Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Department of Materials Application Research AVIC Manufacturing Technology InstituteBeijing 100024China

It is critical to developing electrocatalysts with highly active and cost-effective for oxygen evolution to resolve environmental pollution and energy issues,in which FeNi-based nanomaterials hold a great ***,(Fe_(0.33 )Ni_(0.67))S_(2) and(Fe_(0.33 )Ni_(0.67))S_(2)/reduced graphene oxide(rGO)-x%(x=10,20) composites,which exhibited highly efficient oxygen evolution reaction(OER)electrocatalytic activity under alkaline conditions,were synthesized via a hydrothermal approach and following thermal treatment with sulfur *** from the integrated structure of(Fe_(0.33 )Ni_(0.67))S_(2)and support of conductive graphene backbones,(Fe_(0.33 )Ni_(0.67))S_(2)/rGO-20%electrocatalyst showed the best OER activity with an overpotential of 172 mV at 10 mA·cm^(-2)and Tafel slopes of 45 mV·decade^(-1).The composition,phase,and surface structure of the catalyst were characterized before and after OER *** results indicated that crystal phase of the catalyst was reconstructed to the amorphous crystalline features after OER,with oxidation of iron-nickel sulfide and appearance of Ni-Fe oxo/hydroxide species,which may play a crucial role in the high OER performance as the ***,in a two-electrode system towards overall water splitting with(Fe_(0.33 )Ni_(0.67))S_(2)/rGO-20%/NF and Pt/C/NF as the anode and cathode,respectively,the catalysts exhibited excellent catalytic performance with the voltage of only 1.42 V at 10 mA·cm^(-2).

关键词： Ternary nickel-iron sulfide Reduced graphene oxide(rGO) Electrocatalysts Water oxidation Self-reconstruction

Applying Both Chemical liquefaction and Enzymatic Catalysis Can Increase Production of Agaro-Oligosaccharides from Agarose

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Journal of Ocean University of China 2020年第6期19卷 1371-1377页

作者： JIANG Chengcheng liU zhen liU jie SUN Jianan XU Jiachao li Laihao MAO Xiangzhao College of Food Science and Engineering Ocean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao 266237China Key Laboratory of Aquatic Product Processing Ministry of AgricultureSouth China Sea Fisheries Research InstituteChinese Academy of Fishery ScienceGuangzhou 510300China

Red algae represents an important marine *** high-value utilization of red algae is the production of agarooligosaccharides which have many positive biological ***,the lack of an efficient production route seriously limits the application of *** this study,we established a green route that combines chemical liquefaction and enzymatic catalysis for the efficient production of agaro-oligosaccharides,and we used the production of neoagarotetraose(NA4)as an ***(150 g L^−1)liquefaction by citric acid was controlled with respect to two targets:a 100%liquefaction rate and a high average degree of polymerization(>4)of the liquesced agaro-oligosaccharides,which were then catalyzed byβ-agarase into an oligosaccharides mixture with a high concentration of NA4(30.8 g L^−1)in a 1-L reaction *** purification,we obtained 25.5 g of NA4 with a purity of 92%.This work establishes an easy route for the efficient production of pure agaro-oligosaccharides from agarose.

关键词： neoagarotetraose agarose agarase marine polysaccharide expression

The initial attempt to reveal the emission processes of both mechanoluminescence and room temperature phosphorescence with the aid of circular dichroism in solid state

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Science China Chemistry 2021年第3期64卷 445-451页

作者： Yu Tian Xuekang Yang Yanbin Gong Yunsheng Wang Manman Fang jie Yang Zhiyong Tang zhen li Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China Department of Chemistry Wuhan UniversityWuhan 430072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China

A phenothiazine derivative PtzChol containing non-conjugated chiral cholesterol group was designed and synthesized. By analyzing the single crystal structure of PtzChol carefully, coupled with the circular dichroism(CD) signals before and after grinding, it was found that the introduction of cholesterol produced a positive effect on the production of chiral space group, on mechanoluminescence(ML) and room temperature phosphorescence(RTP), and throughout the entire light-emitting process, the CD signal could well reflect the changes of molecular arrangement.

关键词： mechanoluminescence room temperature phosphorescence circular dichroism phenothiazine cholesterol