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Chalcogen-dependent catalytic properties of RuX2 (X = S/Se/Te) nanoparticles decorated carbon nanofibers for hydrogen evolution in acidic and alkaline media

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Nano Research 2024年第4期17卷 2528-2537页

作者： Chengkai He Yue Wei Jia Xu Yujie Wei Tao Wang Rongfei liu Lvlv Ji Zhun liu sheng Wang School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Physics Shaoxing UniversityShaoxing 312000China Zhejiang Kangjiesi New Material Technology Co. LTDZhuji 311800China

Transition metal dichalcogenides(TMDs),with the general formula MX_(2)(M=Mo/W/Fe/Co/Ni,etc.;X=S/Se/Te),have attracted extensive research interests for hydrogen evolution reaction(HER).Compared with numerous studies on noble-metal-free TMDs,the chalcogen-dependent HER catalytic properties of noble-metal-based TMDs are lack of sufficient research ***,a facile electrospinning-assisted synthetic strategy is proposed to synthesize ruthenium dichalcogenides(RuX_(2),X=S/Se/Te)nanoparticles decorated carbon nanofibers(CNFs).Benefiting from the identical nanofibrous morphology and exposed crystal planes of RuX_(2)(111),the catalytic activities of RuX_(2)@CNFs samples were investigated and compared in a fair and direct *** electrochemical measurements coupled with density functional theory calculations were carried out to probe their intrinsic HER catalytic activities,resulting in the catalytic activity order of RuS_(2)@CNFs>RuSe_(2)@CNFs>RuTe_(2)@CNFs in acidic media and that of RuS_(2)@CNFs>RuTe_(2)@CNFs>RuSe_(2)@CNFs in alkaline *** superior catalytic performance of RuS_(2)@CNFs mainly stems from the relative lower HER energy barriers and thereby the higher intrinsic catalytic activity of RuS_(2)(111),leading to ultralow overpotentials of 44 and 9 mV at 10 mA·cm^(-2) in acidic and alkaline media,***_(2)(111)is endowed with the more optimized Gibbs free energy of hydrogen adsorption(ΔGH*)than RuTe_(2)(111),but RuTe_(2)(111)shows enhanced catalytic property for H_(2)O dissociation and OH-desorption than RuSe_(2)(111),therefore,resulting in the altered catalytic activity sequences for RuSe_(2) and RuTe_(2) in acidic and alkaline media.

关键词： hydrogen evolution reaction transition metal dichalcogenides carbon nanofibers electrocatalysis catalytic activity

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Mesenchymal hamartoma of liver: Magnetic resonance imaging and histopathologic correlation

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World Journal of Gastroenterology 2005年第37期11卷 5807-5810页

作者： Bin-Bin Ye Bing Hu Li-Jun Wang hong-sheng liu Yan Zou Yu-Bin Zhou Zhuang Kang Department of Radiology No. 1 Affiliated Hospital of Sun Yat-Sen University Guangzhou 510080 Guangdong Province China Department of Radiology No.3 Affiliated Hospital of Sun Yat-S-en University Guangzhou 510630 Guangdong Province China

AIM： To describe the imaging features of hepatic mesenchymal hamartoma with emphasis on magnetic resonance imaging （MRI） compared to histopathologic results. METHODS： Spin-echo sequence（SE）,fast spin-echo sequence（FSE） were detected in 12 children （7 males,5 females） with mesenchymal hamartoma of the liver （IVlHL）, aged 1.2 months to 12 years,（ mean age, 6.3 years） by axial, saggital, coronary plain imaging with an Elscint 2.0T MR equipment. Their main symptoms were abdominal mass （5 cases）, enlarged liver （8 cases）, abdominal pain （1 case） and anemia （2 cases）, and negative alpha-fetoprotein. Dynamic enhancement examination was added in 2 cases. RESULTS： Six cases had single mass type of MHL, in which 3 cases had solid masses showing slight low- signal-intensity in TlWI, and irregular high-signal- intensity in T2WI, 1 case had a cystic-solid mixed mass showing several border-clear cysts in a solid mass, 2 cases had cystic masses with multi-septa. Five cases had diffuse and multifocal lesions type of MHL with its signal intensity being similar to that of the solid mass. One case had a combined diffuse and single cystic mass. In the early dynamic enhancement examination, the lesions were slightly circum-enhanced , and the center was enhanced in the later scan images. Inner hepatic vessels were compressed in 5 cases, vena cava and abdominal aortae were compressed in 3 cases. Pathological findings included fiber hyperplasia, hyaline degeneration, biliary duct hyperplasia, Iobule-like array. CONCLUSION： MR imaging is a better way to differentiate and diagnose MHL. MHL may be recognized by its characteristic occurrence in infancy and MR imaging features.

关键词： Hepatic mesenchymal hamartoma Magnetic resonance imaging Histopathologic correlation Children

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Present-day movement characteristics of the Qinghai Nanshan fault and its surrounding area from GPS observation

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Geodesy and Geodynamics 2024年第2期15卷 133-141页

作者： Yang liu Yuxuan Qiu Jialiang liu Luyun Xiong Caijun Xu Jianghui Geng Gang Zheng Tianchen sheng School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan UniversityWuhan 430079China Key Laboratory of Geophysical Geodesy Ministry of Natural ResourcesWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China School of Earth and Environment University of LeedsLeeds LS29JTUK Qinghai Basic Surveying and Mapping Institute Xining 810101China

The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang *** previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transformation role of the fault on its east is not yet *** study uses data fusion to obtain denser GPS observations near the Qinghai Nanshan *** on tectonic characteristics,we establish a block model to investigate the fault slip rate,locking degree,and slip *** results show that the Qinghai Nanshan fault slip rate is characterized by sinistral and convergent *** the sinistral and convergent rates display a decreasing trend from west to *** locking degree and slip deficit are higher in the western segment(with an average of about 0.74 and 1.1 mm/a)and lower in the eastern ***,we construct a strain rate field using GPS observations to analyze the regional strain *** results indicate that along the fault,the western segment shows a larger shear strain rate and negative dilation *** earthquake records show that the frequency of earthquakes is lower near the *** joint results suggest that the western segment may have a higher earthquake *** addition,the insignificant fault slip rate in the eastern segment may indicate that it does not participate in the tectonic transformation among the Riyueshan,Lajishan,and West Qinling faults.

关键词： The Qinghai Nanshan fault Movement characteristics Block model Slip rate GPS

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An injectable,self-healable,and reusable PEDOT:PSS/PVA hydrogel patch electrode for epidermal electronics

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Nano Research 2024年第6期17卷 5479-5490页

作者： Yang Li Yuzhe Gu sheng Qian Shuwen Zheng Yuncong Pang Lele Wang Baoguang liu Shujuan liu Qiang Zhao College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023China State Key Laboratory of Organic Electronics and Information Displays and Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023China

Injectability empowers conductive hydrogels to transcend traditional limitations,unlocking a realm of possibilities for innovative medical,wearable,and therapeutic applications that can significantly enhance patient care and quality of ***,we report an injectable,self-healable,and reusable hydrogel obtained by mixing the concentrated poly(3,4-ethylenedioxythiophene)doped with polystyrene sulfonate(PEDOT:PSS)suspension(~2 wt.%solid content),polyvinyl alcohol(PVA),and *** the presence of reversible borax/hydroxyl bonds and multiple hydrogen bonds,this PEDOT:PSS/PVA hydrogel exhibits notable shear-thinning behavior and self-healing capabilities,enabling it to be injected as a gel fiber from a ***-prepared injectable hydrogel also demonstrates an ultra-low modulus(~2.5 MPa),reduced on-skin impedance(~45%of commercial electrodes),and high signal-to-noise ratio(SNR)(~15-22 dB)in recording of electrocardiography(ECG),electromyography(EMG),and electroencephalogram(EEG)***,the injectable hydrogels can be remolded and reinjected as the reusable electrodes,maintaining nearly identical electrophysiological recording capabilities and brain-computer interface(BCI)performance compared to commercial wet *** their straightforward fabrication,excellent material properties and electronic performance,ease of cleaning,and remarkable reusability,our injectable PEDOT:PSS/PVA hydrogels hold promise for advancements in BCI based electronics and wearable bioelectronics.

关键词： epidermal hydrogel electrodes reusability injectability self-healing electrophysiological recording brain-computer interface

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Full sexual maturity-cycle exposure to environmentally relevant concentrations of 17β-estradiol decreases reproductive capacity of zebrafish

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Journal of Environmental Sciences 2024年第3期137卷 580-592页

作者： Yongkang Zhang Yuanjun Jiang Qian Sun Meng Li sheng Chen Jingyu Liang Chunsheng liu College of Fisheries Huazhong Agricultural UniversityWuhan 430070China School of Environmental Studies China University of GeosciencesWuhan 430074China

17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in ***,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of E2 for the full sexual maturation cycle remain *** this study,zebrafish were treatment with 0,10 or100 ng/L E2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were *** results showed that treatment with E2 lead to increased number of feminization in *** females,E2 decreased cumulative amount of spawning and inhibited the maturation of *** males,E2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of *** adverse effects on sperm might be responsible for the reduced fertilization observed in *** addition,treatment with E2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in ***,these results suggested that treatment with environmentally relevant concentrations of E2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.

关键词： Environmental estrogen Zebrafish Fecundity Gonadal development Endocrine disruption

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Microphase Separation of Semiflexible Ring Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第2期42卷 267-276,I0011页

作者： Dan-Yan Qin sheng-Da Zhao Zhi-Xin liu Jing Zhang Xing-Hua Zhang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the difficult problem of solving the conformation statistics of complex polymers, this study presents a novel and concise conformation statistics theoretical approach based on Monte Carlo and Neural Network method. This method offers a new research idea for investigating the conformation statistics of complex polymers, characterized by its simplicity and practicality. It can be applied to more complex topological structure, more higher degree of freedom polymer systems with higher dimensions, theory research on dynamic self-consistent field theory and polymer field theory, as well as the analysis of scattering experimental data. The conformation statistics of complex polymers determine the structure and response properties of the system. Using the new method proposed in this study, taking the semiflexible ring diblock copolymer as an example, Monte Carlo simulation is used to sample this ring conformation to construct the dataset of polymer. The structure factor describing conformation statistics are expressed as continuous functions of structure parameters by neural network supervised learning. This is the innovation of this work. As an application, the structure factors represented by neural networks were introduced into the random phase approximation theory to study the microphase separation of semiflexible ring diblock copolymers. The influence of the ring's topological properties on the phase transition behavior was pointed out.

关键词： Ring copolymer Diblock copolymers Semiflexible The order-disorder transition

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Molecular mechanism for the unusual enhancement of the second-step chemiluminescence production from the carcinogenic tetrabromohydroquinone and H2O_(2)

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Journal of Environmental Sciences 2024年第7期141卷 330-342页

作者： Zi-Han Wang Chun-Hua Huang Zhi-sheng liu Li Mao Ben-Zhan Zhu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environment and Resources University of Chinese Academy of SciencesBeijing 100049China

We have found recently that two-step intrinsic hydroxyl radical(·OH)-dependent chemiluminescence(CL)could be produced by carcinogenic tetrahaloquinone and H_(2)O_(2).However,the first-step CL was too fast to clearly detect the stepwise generation of·OH and CL,and to distinguish the exact dividing point between the first-step and second-step *** we found that,extremely clear two-step intrinsic CL could be produced by the relative slow reaction of tetrabromohydroquinone(TBHQ)with H_(2)O_(2),which was directly dependent on the two-step·OH ***,the second-step,but not the first-step CL production of TBHQ/H_(2)O_(2)(CRET donor)was markedly enhanced by fluorescein(a typical xanthene dye,CRET acceptor)through a unique chemiluminescence resonance energy transfer(CRET)*** novel CRET system of TBHQ/H_(2)O_(2)/fluorescein was successfully applied for the sensitive detection of TBHQ with the detection limit as low as 2.5μmol/*** findings will help to develop more sensitive and highly efficient CL or CRET systems and specific CL sensor to detect the carcinogenic haloquinones,which may have broad environmental applications.

关键词： Two-step chemiluminescence Bromohydroquinone Hydrogen peroxide Hydroxyl radical CRET

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Superjunction 4H-SiC trench-gate IGBT with an integrated clamping PN diode

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 3-9,27页

作者： Huang Yi Wang Xuecheng Gao sheng liu Bin Zhang hongsheng Han Genquan School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic Science and Engineering Nanjing UniversityNanjing 210008China School of Microelectronics Xidian UniversityXi'an 710126China

In this paper,a novel superjunction 4H-silicon carbide(4H-SiC)trench-gate insulated-gate bipolar transistor(IGBT)featuring an integrated clamping PN diode between the P-shield and emitter(TSD-IGBT)is designed and theoretically *** heavily doping superjunction layer contributes to a low specific on-resistance,excellent electric field distribution,and quasi-unipolar drift *** anode of the clamping diode is in floating contact with the *** the on-state,the potential of the P-shield is raised to the turn-on voltage of the clamping diode,which prevents the hole extraction below the N-type carrier storage layer(NCSL).Additionally,during the turn-off transient,once the clamping diode is turned on,it also promotes an additional hole extraction ***,the potential dropped at the semiconductor near the trench-gate oxide is effectively reduced in the off-state.

关键词： 4H-silicon carbide(4H-SiC) trench-gate superjunction clamping diode

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Response characteristics of PWR primary circuit under SBLOCAs considering steam bypass discharging

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Nuclear Science and Techniques 2024年第6期35卷 189-201页

作者： Shuai Yang Xiang-Bin Li Yu-sheng liu Jia-Ning Xu De-Chen Zhang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy Beijing 102206China Nuclear and Radiation Safety Center MEPBeijing 100084China

Small-break superposed station blackout(SBO)accidents are the basic design accidents of nuclear power *** the condition of a small break in the cold leg,SBO further increases the severity of the accident,and the steam bypass discharg-ing system(GCT)in the second circuit can play an important role in guaranteeing core *** explore the influence of the GCT on the thermal-hydraulic characteristics of the primary circuit,RELAP5 software was used to establish a numerical model based on a typical pressurized water reactor nuclear power *** different small breaks in the cold-leg super-posed SBO were selected,and the impact of the GCT operation on the transient response characteristics of the primary and secondary circuit systems was *** results show that the GCT plays an indispensable role in core heat removal during an accident;otherwise,core safety cannot be *** GCT was used in conjunction with the primary safety injection system during the placement *** the break diameter was greater than a certain critical value,the core cooling rate could not be guaranteed to be less than 100 K/h;however,the core remained in a safe state.

关键词： Steam bypass discharging Pressurized water reactor SBLOCA Numerical simulation

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Trench gate GaN IGBT with controlled hole injection efficiency

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 10-16页

作者： Huang Yi Li Yueyue Gao sheng Wang Qi liu Bin Han Genquan School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic Science and Engineering Nanjing UniversityNanjing 210008China School of Microelectronics Xidian UniversityXi’an 710126China

In this paper,a novel trench gate gallium nitride(GaN)insulated gate bipolar transistor(GaN IGBT),in which the collector is divided into multiple regions to control the hole injection efficiency,is designed and theoretically *** incorporation of a P+/P-multi-region alternating structure in the collector region mitigates hole injection within the collector *** the device is in forward conduction,the conductivity modulation effect results in a reduced storage of carriers in the drift *** a result,the number of carriers requiring extraction during device turn-off is minimized,leading to a faster turn-off *** results illustrate that the GaN IGBT with controlled hole injection efficiency(CEH GaN IGBT)exhibits markedly enhanced performance compared to conventional GaN IGBT,showing a remarkable 42.2%reduction in turn-off time and a notable 28.5%decrease in turn-off loss.

关键词： gallium nitride insulated gate bipolar transistor(GaN IGBT) hole injection trench gate turn-off loss

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