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China Ocean Engineering 2024年第3期38卷 394-407页

作者： HU Ze-bo LIU Zhen LI Peng guo hai-yan.ren xiao-hui HOU Hao HAO Lian-hong College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China

In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined *** experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the *** rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged *** experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity *** the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced *** the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’*** the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.

关键词： marine riser vortex-induced vibration tandem arrangement roughness interference effect

Experimental Study on Vortex-Induced Vibration of Rough Risers with Coupling Interference Effect Under Side-by-Side Arrangement

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China Ocean Engineering 2024年第1期38卷 18-28页

作者： HU Ze-bo LIU Zhen LI Peng guo hai-yan WANG Shu-bing ren xiao-hui HOU Hao WANG Ye-shuo College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China CHEC Dredging Co. LtdShanghai 200136China

A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined *** roughness of the riser was characterized by arranging different specifications of surface attachments on the surface of the *** risers with three different roughnesses were arranged side by side with smooth risers to explore the VIV response of the riser under the combined action of roughness and interference effect,and to reveal the coupling mechanism between roughness and interference *** experimental results show that,compared with that of a smooth riser,the VIV of a rough riser under the coupling interference effect has a wider"lock-in"region,and the displacement decreases more significantly at a high reduced velocity,which is more likely to excite higher-order modes and frequency *** addition,the displacement response and frequency response of the smooth riser are not significantly affected by wake interference from the rough riser,which is caused by the decrease of the wake region due to the delay of the boundary layer separation point of the rough riser.

关键词： marine riser vortex-induced vibration side-by-side arrangement roughness interference effect

Effect of Chinese Medicine in Patients with COVID-19: A Multi-center Retrospective Cohort Study

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Chinese Journal of Integrative Medicine 2024年第11期30卷 974-983页

作者： ZHAO guo-zhen yan Shi-yan LI Bo guo Yu-hong SONG Shuang HU Ya-hui guo Shi-qi HU Jing DU Yuan LU hai-tian YE Hao-ran ren Zhi-ying ZHU Ling-fei XU xiao-long SU Rui LIU Qing-quan Beijing Hospital of Traditional Chinese Medicine Capital Medical University Beijing Institute of Traditional Chinese Medicine School of Clinical Medicine Beijing University of Chinese Medicine School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese Medicine College of Integrated Chinese Medicine Tianjin University of Traditional Chinese Medicine

Objective: To evaluate the effectiveness and safety of Chinese medicine(CM) in the treatment of coronavirus disease 2019(COVID-19) in China. Methods: A multi-center retrospective cohort study was carried out, with cumulative CM treatment period of 3 days during hospitalization as exposure. Data came from consecutive inpatients from December 19, 2019 to May 16, 2020 in 4 medical centers in Wuhan, China. After data extraction, verification and cleaning, confounding factors were adjusted by inverse probability of treatment weighting(IPTW), and the Cox proportional hazards regression model was used for statistical analysis. Results:A total of 2,272 COVID-19 patients were included. There were 1,684 patients in the CM group and 588 patients in the control group. Compared with the control group, the hazard ratio(HR) for the deterioration rate in the CM group was 0.52 [95% confidence interval(CI): 0.41 to 0.64, Prenal function in the CM group was smaller. Conclusion: This real-world study indicates that the combination of a full-course CM therapy on the basic conventional treatment, may safely reduce the deterioration rate and all-cause mortality of COVID-19patients. This result can provide the new evidence to support the current treatment of COVID-19. Additional prospective clinical trial is needed to evaluate the efficacy and safety of specific CM interventions.(Registration No. ChiCTR2200062917)

关键词： Chinese medicine all-cause mortality cohort study coronavirus disease 2019 deterioration rate

Metamorphic P-T conditions and ages of garnet-biotite schists in the Dahongshan Group from the southwestern yangtze Block

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Acta Geochimica 2024年第4期43卷 707-718页

作者： Jun-xiao Ma Guang-shu yang Yong-feng yan xiao-Fei Xu Yun-hua ren hui Zhao xiao-jun Zheng Yuan Qin Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Geological Team 306 of Yunnan Non-Ferrous Metals Geological Bureau Kunming 650217China Yunnan Provincial Bureau of Non-Ferrous Geology Kunming 650051China

The Dahongshan Group,situated at the southwestern margin of the yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the *** paper investigates the garnet-biotite schist from the Laochanghe Formation of the Dahongshan Group,employing an integrated approach that includes petrological analysis,phase equilibrium modeling,and zircon U-Pb *** schist is mainly composed of garnet,biotite,plagioclase,quartz,rutile,and *** equilibrium modeling revealed the peak metamorphic conditions of 8-9 kbar and 635-675°*** further integrating the prograde metamorphic profile of garnet and geothermobarometric results,a clockwise P-T metamorphic evolution path is constructed,which includes an increase in temperature and pressure during the prograde ***-ICP-MS zircon U-Pb dating and zircon Ti thermometry constrains the post-peak metamorphic age of 831.2±7.2 *** with previously reported results,it is revealed that the southwestern margin of the yangtze Block experienced a large-scale regional metamorphism during the Neoproterozoic(890-750 Ma),which is related to the collisional orogenic *** may be associated with the late-stage assembly of the Rodinia supercontinent or with local compression and subduction processes during the breakup of the Rodinia supercontinent.

关键词： Southwestern yangtze Block Dahongshan Group Phase equilibrium modeling Zircon U-Pb dating Neoproterozoic metamorphism

Nomogram based on liver stiffness and spleen area with ultrasound for posthepatectomy liver failure:A multicenter study

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World Journal of Gastroenterology 2024年第27期30卷 3314-3325页

作者： Guang-Wen Cheng yan Fang Li-Yun Xue xiao-hui Qiao Xue-Qi Li yan Zhang Jia guo xiao-yan Xie Hong Ding Department of Ultrasound Huashan HospitalFudan UniversityShanghai 200040China Department of Ultrasound Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Medical Ultrasonics Institute of Diagnostic and Interventional UltrasoundSun Yat-sen University First Affiliated HospitalGuangzhou 510080Guangdong ProvinceChina Institute of Ultrasound in Medicine and Engineering Shanghai Cancer CenterShanghai 200040China Department of Ultrasound Eastern Hepatobiliary Surgical HospitalSecond Military Medical UniversityShanghai 200433China Department of Ultrasound National Clinical Research Center for Aging and MedicineHuashan HospitalFudan UniversityShanghai 200040China

BACKGROUND Liver stiffness(LS)measurement with two-dimensional shear wave elastography(2D-SWE)correlates with the degree of liver fibrosis and thus indirectly reflects liver function *** size of the spleen increases due to tissue proliferation,fibrosis,and portal vein congestion,which can indirectly reflect the situation of liver fibrosis/*** was reported that the size of the spleen was related to posthepatectomy liver failure(PHLF).So far,there has been no study combining 2D-SWE measurements of LS with spleen size to predict *** prospective study aimed to investigate the utility of 2D-SWE assessing LS and spleen area(SPA)for the prediction of PHLF in hepatocellular carcinoma(HCC)patients and to develop a risk prediction *** To investigate the utility of 2D-SWE assessing LS and SPA for the prediction of PHLF in HCC patients and to develop a risk prediction *** This was a multicenter observational study prospectively analyzing patients who underwent hepatectomy from October 2020 to March *** 1 wk before partial hepatectomy,ultrasound examination was performed to measure LS and SPA,and blood was drawn to evaluate the patient’s liver function and other *** absolute shrinkage and selection operator logistic regression and multivariate logistic regression analysis was applied to identify independent predictors of PHLF and develop a *** performance was validated *** diagnostic performance of the nomogram was evaluated with receiver operating charac-teristic curve compared with the conventional models,including the model for end-stage liver disease(MELD)score and the albumin-bilirubin(ALBI)*** A total of 562 HCC patients undergoing hepatectomy(500 in the training cohort and 62 in the validation cohort)were enrolled in this *** independent predictors of PHLF were LS,SPA,range of resection,blood loss,international normalized ratio,and total *** diagnostic performanc

关键词： Shear-wave elastography Spleen Hepatectomy Posthepatectomy liver failure Hepatocellular carcinoma

Crystalline-amorphous M@MN_x(M=Co,Fe,Ni)encapsulated in nitrogen-doped carbon for enhanced efficient and durable hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1547-1556页

作者： yang yang xiao-Chuan Duan Shao-hui guo Xian-Ming Zhang College of Materials Science and Engineering College of ChemistryKey Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of TechnologyYuci030600China

Developing earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is important for the sustainable energy ***,efficient and stable heterocatalysts consisting of crystalline-amorphous M@MN_(x)(M=Co,Fe,Ni)encapsulated in N-doped carbon layers supported with N-doped graphene sheets(denoted as M@MN_(x)@NC-NG)are synthesized by facile hydrothermal reaction and nitridation *** the nitriding process,metal ions in M(tzbc)_2(H_(2)O)_4(tzbc=4-(1H-1,2,4-triazol-1-yl)benzoic acid)complexes are reduced to crystalline M cores,accompanied by the formation of amorphous MN_(x)shells;the tzbc ligands are insitu carbonized to form outermost N-doped carbon(NC)layers that connect with inner MN_(x)via M-N-C motifs inherited from the complex precursors and inhibit the transition of MN_(x)from amorphous to crystalline *** Co@CoN_(x)@NC-NG catalyst exhibits excellent HER activity with small overpotentials of 45 and 64 mV at a cathode current density of 10 mA·cm^(-2)and low Tafel slopes of 40 and 85 mV·dec^(-1)in 0.5 mol·L^(-1)H_(2)SO_4 and1.0 mol·L^(-1)KOH electrolytes,*** Co@CoN_(x)@NC-NG retains 97%of the initial overpotential after 100,000 s in both acidic and alkaline *** outstanding HER performance originates from the crystalline-amorphous Co@CoN_(x)that redistributes electrons around the heterointerfaces,facilitating the conversion process of H^(+)/H_(2)O to hydrogen and thereby promoting HER *** outermost NC layers serve as the armor of Co@CoN_(x),and graphene nanosheets act as carriers of egg-like Co@CoN_(x)@NC and conduction paths for electron shuttles,ensuring stable and continuous electrocatalytic hydrogen production.

关键词： Hydrogen evolution reaction Electrocatalysts Iron group metals Heterojunction Crystalline-amorphous structure

Influences of oscillation on the physical stability and explosion characteristics of solid-liquid mixed fuel

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Defence Technology（防务技术） 2024年第10期40卷 191-198页

作者： Chi Zhang Ge Song hui guo Jiafan ren Chunhua Bai Beijing Aerospace Propulsion Institute Beijing 100076China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The stratification phenomenon resulting from differences in the physical properties of solid-liquid components seriously affect the final combustion and explosion characteristics of mixed fuel under the action of *** effects of oscillation on the physical stability of mixed fuel with two solid-liquid ratios and three liquid component distribution ratios have been investigated using a self-designed experimental system at oscillation frequencies of 60-300 r/*** explosion characteristics of mixed fuel before and after oscillation are gained from a 20 L spherical explosion container *** the mass ratio of liquid components is controlled at 66.9%,64.7%,62.6%the final explosion characteristics are stable,with a maximum difference of only 0.71%.The volume of liquid fuel precipitation increases with increasing oscillation frequency when the mass ratio of liquid components reaches 71.7%,69.6%,67.7%.The fuel explosion overpressure after oscillation decreases with increasing liquid precipitation volume,and the repeatability is poor,with a maximum standard deviation of 82.736,which is much higher than the ratio without *** controlling the mass ratio of liquid components of the mixed fuel can effectively combat the impact of oscillation on the physical state and maintain the stability of the final explosion characteristics.

关键词： Solid-liquid mixed fuel Physical stability Explosion characteristics

Roles of Cu doping in YbZn_(2)Sb_(2) for thermoelectric performance enhancement

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Rare Metals 2024年第6期43卷 2869-2875页

作者： Xiong Zhang hai-hui Li xiao-Liang Cao Bin Zhang Hong Wu Yu Zhang Guang Han guo-Yu Wang Hao-Shuang Gu xiao-Yuan Zhou College of Physics and Electronic Science Hubei Normal UniversityHuangshi 435002China Analytical and Testing Center Chongqing UniversityChongqing401331China School of Science Chongqing University of Posts and Telecommunications.Chongqing 400065 China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials-Hubei Key Laboratory of Ferro&Piezoelectric Materials and Devices Faculty of Physical and Electronic SciencesHubei UniversityWuhan 430062China College of Physics Chongqing UniversityChongqing 401331China

Recent research shows that increasing the carrier density after orbital alignment in AZn_(2)Sb_(2) (A=Ca,Yb,Eu,Sr,Mg)Zintl compounds yields remarkable results with regard to enhanced thermoelectric ***,research on carrier density increase via doping in these compounds is *** this study,we introduced Cu into the Zn sites in YbZn_(2)Sb_(2) and examined the thermoelectric properties.

关键词： properties doping performance

High-Temperature Stability of Mg-1Al-12Y Alloy Containing LPSO Phase and Mechanism of Its Portevin-Le Chatelier(PLC)Effect

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 982-998页

作者： Qian-Long ren Shuai Yuan Shi-Yu Luan Jin-hui Wang xiao-Wei Li xiao-Yu Liu Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and FormingQinghai UniversityXining810016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China

In this study,the high-temperature stability and the generation mechanism of the Portevin-Le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusting the content of long-period stacking ordered(LPSO)*** was found that the content of LPSO phases in the alloys differed the most after heat treatment at 530℃for 16 h and 24 h,with values of 13.56%and 3.93%***,high-temperature tensile experiments were conducted on these two alloys at temperatures of 150℃,200℃,250℃,and 300℃.The results showed that both alloys exhibited the PLC effect at temperatures ranging from 150 to 250℃.However,at a temperature 300℃,only the alloy with a greater concentration of LPSO phases exhibited the PLC effect,whereas the alloy with a lower proportion of LPSO phases did not exhibit this ***,both alloys exhibited remarkable high-temperature stability,with the alloy containing a greater percentage of LPSO phases also demonstrating superior *** underlying mechanism for this phenomenon lies in the exceptional high-temperature stability exhibited by the second phase within the ***,the LPSO phase effectively obstructs the movement of dislocations,and it also undergoing kinking to facilitate plastic deformation of the *** results indicate that the PLC effect can be suppressed by reducing dislocation pile-up at grain boundaries,which leads to a decrease in alloy plasticity but an increase in *** presence of the PLC effect in the WA121 alloy is attributed to the abundant dispersed second phase within the alloy,which initially hinders the movement of dislocations,leading to an increase in stress,and subsequently releases the dislocations,allowing them to continue their movement and thereby reducing in stress.

关键词： Magnesium alloy Long-period stacking ordered(LPSO)phase Portevin-Le Chatelier effect High temperature

Hydrogen production from hydrolysis of NaBH_(4) solution over Co-Fe-B@g-C_(3)N_(4)/NF thin film catalyst

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Rare Metals 2024年第6期43卷 2648-2659页

作者： yan Wang Jia-Xin Ma Jian ren Di Zhang Feng-yan Xu Ke Zhang Zhong-Qiu Cao Qiu-Ju Sun guo-De Li Shi-Wei Wu Hong-hui Chen College of Chemistry and Chemical Engineering Shenyang Normal UniversityShenyang 110034China Experimental Center Shenyang Normal UniversityShenyang 110034China Hunan Shande Energy Storage New Materials Research Institute Limited Company Changde 415000China

In this study,the double loaded Co-Fe-B@g-C_(3)N_(4)/NF(NF:Ni foam)thin film catalysts were prepared for the first time via chemical deposition method at room *** optimizing the reducing agent concentration to 0.9 mol·L^(-1),the as-obtained Co-Fe-B@g-C_(3)N_(4)/NF exhibited the twisted ribbon structure with more distinct three-dimensional hierarchy and the smaller particle size,showing the good catalytic property for the hydrolysis of NaBH_(4)*** H_(2)generation rate of Co-Fe-B@g-C_(3)N_(4)/NF and binary Co-B@g-C_(3)N_(4)/NF under visible light irradiation surpassed the value under natural *** apparent activation energy of Co-Fe-B@g-C_(3)N_(4)/NF(45.0 kJ·mol^(-1))under visible light irradiation was obviously reduced when compared with the natural condition(48.4 kJ·mol^(-1))and binary Co-B@g-C_(3)N_(4)/NF(60.6 kJ·mol^(-1))under visible light ***,the catalytic performance of the optimized Co-Fe-B@g-C_(3)N_(4)/NF thin film catalyst was superior to most of the reported non-noble metal and even noble metal ***,it illustrated that the catalytic H_(2)production performance of Co-Fe-B@g-C_(3)N_(4)/NF thin film was distinctly improved after the introduction of light and multicomponent recombination.

关键词： Sodium borohydride Co-Fe-B@g-C_(3)N_(4)/NF catalyst Chemical deposition Hydrogen production