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Journal of Iron and Steel Research International 2024年第2期31卷 377-388页

作者： Tao Pan Hong-chun Zhu Zhou-hua jiang Hua-bing Li Rui Zhang hao Feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh *** results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width ***,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium *** melt rate increases,both the molten pool depth and the mushy width *** is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the *** nonlinear increment in sensible heat leads to a nonlinear increase in the mushy *** addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then *** melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time

Straw addition increases enzyme activities and microbial carbon metabolism activities in bauxite residue

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Journal of Environmental Sciences 2024年第1期135卷 332-344页

作者： hao Wu Wei Sun Feng Zhu Yifan jiang Shiwei Huang Johnvie Goloran Shengguo Xue School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Environment and Science Griffith UniversityBrisbaneQLD 4072Australia

Recovery of microbial functions is one of the critical processes in the nutrient cycling of bauxite residue for improving *** is considered to be effective to increase microbial diversity and drive the development of the microbial community,but its effect on microbial carbon metabolism has not been *** present study evaluated the effects of phosphogypsum(PG),straw(SF)and phosphogypsum plus straw(PGSF)on physicochemical properties,enzyme activities,and microbial carbon metabolism activities in bauxite *** 180 days incubation,PG,SF and PGSF treatment significantly reduced the residue pH from 10.85 to 8.64,9.39 and 8.06,*** to CK treatment,SF treatment significantly increased the content of total organic carbon(TOC)and organic carbon fractions(DOC,MBC,EOC,and POC).In addition,straw addition significantly increased glucosidase,cellulose,urease,and alkaline phosphatase by 7.2-9.1 times,5.8-7.1 times,11.1-12.5 times,and 1.1-2.2 times,*** Biolog results showed that straw addition significantly increased microbial metabolic activity(AWCD)and diversity in bauxite *** analysis indicated total nitrogen(TN)and carbon fractions(POC,MBC and DOC)were the most important environmental factors affecting microbial metabolic activity and diversity in bauxite *** findings provided us with a biogeochemical perspective to reveal soil formation in bauxite residue and suggested that nutrient supplement and regulation of salinity-alkalinity benefit the establishment of microbial communities and functions in bauxite residue.

关键词： Bauxite residue Labile organic carbon fractions Enzyme activities Community-level physiological profiles Soil formation in bauxite residue

Analysis and Optimization of the Electrohydraulic Forming Process of Sinusoidal Corrugation Tubes

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Fluid Dynamics & Materials Processing 2024年第4期20卷 873-887页

作者： Da Cai Yinlong Song hao jiang Guangyao Li Junjia Cui State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Hunan UniversityChangsha410082China

Aluminum alloy thin-walled structures are widely used in the automotive industry due to their advantages related to light weight and *** can be produced at room temperature by the electrohydraulic forming *** the present study,the influence of the related parameters on the forming quality of a 6063 aluminum alloy sinusoidal corrugation tube has been *** particular,the orthogonal experimental design(OED)and central composite design(CCD)methods have been *** the range analysis and variance analysis of the experimental data,the influence degree of wire diameter(WD)and discharge energy(DE)on the forming quality was *** regression analysis was performed using the response surface methodology.A prediction model for the attaching-die state coefficient was established *** following optimal arrangement of parameters was obtained(WD=0.759 mm,DE=2.926 kJ).The attaching-die state coefficient reached the peak value of *** optimized wire diameter and discharge energy for a better attaching-die state could be screened by CCD compared with *** response surface method in CCD was more suitable for the design and optimization of the considered process parameters.

关键词： Electrohydraulic forming aluminum alloy tube process parameters attaching-die state 1 Introduction

Dynamic Identification and Evolution of Urban-suburban-rural Transition Zones Based on the Blender of Natural and Humanistic Factors: A Case Study of Chengdu, China

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Chinese Geographical Science 2024年第5期34卷 791-809页

作者： DENG Wei jiang Zhenyuan ZHANG Shaoyao REN Ping ZHANG hao WANG Zhanyun The Faculty Geography Resources Science Sichuan Normal UniversityChengdu 610101China Sustainable Development Re-search Center of Resources and Environment in Western Sichuan Sichuan Normal UniversityChengdu 610101China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heterogeneity across territorial *** a super megacity in western China,Chengdu’s rapid urbanization has driven the evolution of U-S-R spaces,resulting in a sequential *** promote the high-quality spatial development of urban-rural region in a structured and efficient manner,it is essential to con-duct a scientific examination of the multidimensional interconnection within the U-S-RTZ *** proposing a novel identifica-tion method of U-S-RTZ and taking Chengdu,China as a case study,grounded in a blender of natural and humanistic factors,this study quantitatively delineated and explored the spatial evolutions of U-S-RTZ and stated the optimization orientation and sustainable devel-opment strategies of the production-living-ecological spaces along the U-S-R *** results show that:1)it is suitable for the quantitative analysis of U-S-RTZ by established three-dimensional identification system in this study.2)In 1990-2020,the urban-sub-urban transition zones(U-STZ)in Chengdu have continuously undergone a substantial increase,and the scale of the suburban-rural transition zones(S-RTZ)has continued to expand slightly,while the space of rural-ecological transition zones(R-ETZ)has noticeably compressed.3)The landuse dynamics within U-S-RTZ has gradually increased in *** main direction of landuse transition was from farmland to construction land or woodlands,with the expansion of construction land being the most significant.4)R-ETZ primarily focus on ecological functions,and there is a trade-off relationship between the production-ecological function within the S-RTZ,and in the U-STZ,production-living composite functions are *** study emphasizes the importance of elastic planning and precise governance within the U

关键词： transition zone urban-suburban-rural zones spatial identification evolution mechanism Chengdu,China

Long-term tadalafil once daily in Chinese men with erectile dysfunction:a 2-year final analysis of a post-marketing,multicenter,randomized,open-label trial

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Asian Journal of Andrology 2024年第3期26卷 282-287页

作者： Hui jiang Lian-Ming Zhao Su Yan Ji-Hong Liu Zhao-Hui Zhu Jin-Dan Luo Yu-Tian Dai Fu-Biao Li hao-Cheng Lin zhi-Chao Zhang Department of Urology Peking University First HospitalBeijing 100000China Department of Urology Peking University Third HospitalBeijing 100191China Department of Urology Peking Union Medical College HospitalBeijing 100730China Department of Urology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Urology Union Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Urology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Departmentof Andrology Nanjing Drum Tower HospitalNanjing 210008China Department of Andrology The First Hospital of Jilin UniversityChangchun 130021China Andrology Center Department of UrologyPeking University First HospitalBeijing 100034China

The long-term safety and effectiveness of once-daily tadalafil is crucial,but limited data are available in Chinese patients witherectile dysfunction(ED).In this post-marketing,multicenter,randomized,open-label trial with 2-year follow-up,635 ED caseswere randomized to receive daily oral tadalafil 2.5 mg or 5 mg for 3 months,of whom 580 continued once-daily tadalafil 5 mg for21 ***-emergent adverse events in the 12-month and 24-month period were similar,with the most common beingviral upper respiratory tract infection,upper respiratory tract infection,and *** improvement from baseline inthe International Index of Erectile Function-Erectile Function(IIEF-EF)score was detected at month 12(least squares mean[LSM]change:7.9,95%confidence interval[CI]:7.5–8.4,P<0.001)and was maintained to month 24(LSM change:8.6,95%CI:8.1–9.0,P<0.001).The proportions of patients regaining normal erectile function(IIEF-EF score≥26)were 43.7%and 48.0%at months 12 and 24,*** Assessment Questionnaire results showed improved erection function in 97.5%ofpatients and improved ability to engage in sexual activity in 95.9%of patients at month 12;these values were 96.1%and 95.0%at month 24,*** quality of sexual life score based on the Sexual Life Quality Questionnaire(SLQQ)was increased by52.2%at month 12 and by 55.3%at month 24(both P<0.001).The treatment satisfaction score determined by SLQQ(mean±standard deviation)was 62.4±21.0 at month 12 versus 65.9±20.2 at month ***-year daily application of tadalafil 5mg in Chinese men with ED showed a favorable safety profile and durable improvement in sexual performance and satisfaction.

关键词： clinical trial erectile dysfunction long-term safety once-daily dosing tadalafil

Radical involved reactive wetting and retarding mechanism of alumina refractory ceramic by molten slags under weak static magnetic field

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Journal of Iron and Steel Research International 2024年第6期31卷 1355-1366页

作者： Sheng-hao Li Ao Huang Fan-bo Zeng Hui Peng hao-ran Wei Xue-chun Huang Sheng-qiang Song Hua-zhi Gu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory *** static magnetic field is a promising solution for improvement in the slag resistance of *** wetting of alumina refractory ceramics with different basicities of high alumina slags under a weak static magnetic field was analyzed,given that a weak static magnetic field can affect the corrosion behavior of refractory *** slag S_(3) as an example,when there was an external static magnetic field of 1.0 mT at 1600 ℃,the thickness of calcium aluminate reaction layer at the interface decreased by 36.7%,the denting depth of interface decreased by 35.6%,and the apparent wetting angle increased by 20%.The living radicals and their formation path in oxide melts were verified by first-principles calculation combined with electron paramagnetic resonance spectroscopy *** influence of the flux density of a weak static magnetic field on the wetting behavior of slags was also *** contact angle of the slags increased owing to the inhibitory effect of magnetic field on the radicalinvolved reaction at the interface of the slag and the alumina refractory *** relationships between the magnetic flux density,diffusion coefficient,slag microstructure(hyperfine coupling constant),and contact angle were *** provides a theoretical basis for the field control of radical involved reactive wetting between inorganic oxide slags and solid oxide ceramics.

关键词： Alumina refractory ceramic Molten slag Weak magnetic field effect Reactive wetting Free radical

AB_(2)-type rare earth-based compounds with C-15 structure:Looking for reversible hydrogen storage materials

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Journal of Rare Earths 2024年第5期42卷 803-816,I0001页

作者： hao Shen Junxian Zhang Valerie Paul-Boncour Ping Li zhinian Li Yuanfang Wu Lijun jiang National Engineering Research Center of Nonferrous Metals Materias and Products for New Energy GRINM Group Co.LtdBeijing00088China Univ Paris Est Creteil CNRSICMPEUMR 71822 rue Henri Dunant94320ThiaisFrance Institute for Advanced Materials and Technology University of Science and TechnologyBeijing100083China GRIMAT Engineering Institute Co. Ltd.Beijing101407China

AB_(2)-type(A=rare earth,B=transition metal)intermetallic compounds with C15 structure can easily absorb large amount of hydrogen,showing their potential use as hydrogen storage *** crucial problem hindering their application is hydrogen induced amorphization(HIA),which leads to the irreversible hydrogen sorption *** stability of the AB_2 Laves phase compounds,the structural properties,the hydrogenation properties and the controlling factors of HIA are discussed in this *** with other factors,the atomic radii ratio r_A/r_B is the most important one influencing the ***-element substitution is an efficient way to suppress or limit HIA and may enable AB_2 compounds to be suitable for hydrogen storage.

关键词： Rare earth-based AB_2-type compounds Hydrogenation properties Hydrogen induced amorphization Elemental substitution

Self-assembly Induced by Complexation of Diblock Copolyelectrolytes and Oppositely Charged Homopolymers

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Chinese Journal of Polymer Science 2024年第9期42卷 1321-1332,I0006页

作者： Ling Zhao zhi-Yuan Yin Jia-Di jiang Er-Qiang Chen Shuang Yang Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Mater Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

We investigate the solution self-assembly of a mixture of positively charged homopolymers and AB diblock copolymers,in which the A blocks are negatively charged,and the B blocks are *** electrostatic complexation between oppositely charged polymers drives the formation of many ordered *** microstructures and phase diagrams are calculated using self-consistent field theory(SCFT)based on an ion-pair model with an equilibrium constant K to characterize the strength of binding between positively and negatively charged *** effects of the charge ratio,representing the ratio of charges from the homopolymer over all charges from polymers in the system,on the ordered structure are systematically studied,both for hydrophobic and hydrophilic A *** charge ratio plays an important role in determining the phase boundaries in the phase diagram of salt concentration versus polymer *** also provide information about the varying tendency of the domain spacing and core size of the spherical phase when the charge ratio is changed,and the results are in good agreement with *** studies provide a deep understanding of the self-assembled microstructures of oppositely charged diblock copolymer-homopolymer systems.

关键词： Self-assembly Polyelectrolyte complexation Self-consistent field theory Ion-pair

Measurement of the high energyγ-rays from heavy ion reactions usingČerenkov detector

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Nuclear Science and Techniques 2024年第2期35卷 123-130页

作者： Da-Wei Si Yan Zhou Sheng Xiao zhi Qin Dong Guo Yu-hao Qin Yi-Jie Wang Bo-Yuan Zhang Bai-Ting Tian zhi-Gang Xiao Department of Physics Tsinghua UniversityBeijing 100084China

The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.

关键词： Bremsstrahlungγ-rays Čerenkov Geant4 Energy resolution Direction reconstruction Hough transform

Systemic immune-inflammation index combined with pediatric appendicitis score in assessing the severity and prognosis for paediatric appendicitis

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2565-2573页

作者： Li-Ming Guo zhi-Hui jiang Hong-Zhen Liu Department of General Surgery Qingdao Women and Children’s HospitalQingdao 266000Shandong ProvinceChina Department of Pediatric Surgery Children's Hospital Affiliated to Shandong UniversityJinan 250022Shandong ProvinceChina Department of Pediatric Surgery Jinan Children's HospitalJinan 250022Shandong ProvinceChina

BACKGROUND Pediatric appendicitis is a common cause of abdominal pain in children and is recognized as a significant surgical emergency.A prompt and accurate diagnosis is essential to prevent complications such as perforation and *** To investigate the predictive value of the systemic immune-inflammation index(SII)combined with the pediatric appendicitis score(PAS)for the assessment of disease severity and surgical outcomes in children aged 5 years and older with *** Clinical data of 104 children diagnosed with acute appendicitis were *** participants were categorized into the acute appendicitis group and chronic appendicitis group based on disease presentation and further stratified into the good prognosis group and poor prognosis group based on *** SII and PAS were measured,and a joint model using the combined SII and PAS was constructed to predict disease severity and surgical *** Significant differences were observed in the SII and PAS parameters between the acute appendicitis group and chronic appendicitis *** analysis showed associations among the SII,PAS,and disease severity,with the combined SII and PAS model demonstrating significant predictive value for assessing disease severity[aera under the curve(AUC)=0.914]and predicting surgical outcomes(AUC=0.857)in children aged 5 years and older with *** The study findings support the potential of integrating the SII with the PAS for assessing disease severity and predicting surgical outcomes in pediatric appendicitis,indicating the clinical utility of the combined SII and PAS model in guiding clinical decision-making and optimizing surgical management strategies for pediatric patients with appendicitis.

关键词： Systemic immune-inflammation index Pediatric appendicitis score Disease severity Surgical outcomes Risk factor Logistic regression Receiver operating characteristic analysis