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Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD

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Journal of Hydrodynamics 2024年第2期36卷 363-377页

作者： Hui Liu Yun-fa Lin Yong-guang Cheng Song Xue Mao-jia Tang Jian Zhang Jia-yi fan State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Dongfang Electric Machinery Co. Ltd.Deyang618000China

The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of *** this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization *** sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was *** results show that GVs dominate the transient characteristics by controlling the change of *** GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial *** directly affect the runner *** RBs’closing speed can further reduce the rotational speed and the maximum reverse axial *** safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method.

关键词： Bulb turbine load rejection transient process double regulation closing law optimization computational fluid dynamics(CFD)

Subclinical paraganglioma of the retroperitoneum:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2672-2677页

作者： Li-Min Kang fa-Kun Yu Fu-Wei Zhang Lei Xu Department of Hepatobiliary and Pancreatic Surgery Puer People's HospitalPuer 665000Yunnan ProvinceChina

BACKGROUND Paraganglioma(PGL)located in the retroperitoneum presents challenges in diagnosis and treatment due to its hidden location,lack of specific symptoms in the early stages,and absence of distinctive manifestations on *** SUMMARY A 56-year-old woman presented with a left upper abdominal mass discovered 1 wk ago during a physical *** did not have a history of smoking,alcohol consumption,or other harmful habits,no surgical procedures or infectious diseases,and had a 4-year history of *** admission,she did not exhibit fever,vomiting,or abdominal *** examination indicated mild percussion pain in the left upper abdomen,with no palpable enlargement of the liver or *** tests and tumor markers showed no significant *** computed tomography and magnetic resonance imaging of the upper abdomen revealed a cystic solid mass in the left epigastrium measuring approximately 6.5 cm×4.5 cm,with inhomogeneous enhancement in the arterial phase,closely associated with the lesser curvature of the stomach and the *** patient underwent laparoscopic resection of the retroperitoneal mass,which was successfully removed without tumor rupture.A 12-month postoperative follow-up period showed good *** This case report details the successful laparoscopic resection of a retroperitoneal subclinical PGL,resulting in a good recovery observed at the 12-month ***,the patient also experienced unexpected cure of hypertensive disease.

关键词： Paraganglioma Retroperitoneal anatomy Subclinical Pheochromocytoma Laparoscopy Case report

Emerging role of liquid biopsy in rat sarcoma virus mutated metastatic colorectal cancer:A case report

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 234-243页

作者： João Gramaça Isabel Gomes Fernandes Carolina Trabulo Joana Gonçalves Rita Gameiro dos Santos Adriano Baptista idília Pina Centro Hospitalar Barreiro Montijo Centro Hospitalar Barreiro MontijoSetúbalBarreiro 2830-003Portugal Medical Oncology Unit Centro Hospitalar Barreiro MontijoSetúbalBarreiro 2830-003Portugal

BACKGROUND In patients with metastatic colorectal cancer(mCRC),the treatment options are limited and have been proved to be affected by rat sarcoma virus(RAS)mutational *** RAS wild-type(wt)patients,the combination of antiepidermal growth factor receptor(EGFR)monoclonal antibodies with chemotherapy(CT)is more effective than CT *** the other hand,RAS-mutated patients are not eligible for treatment with anti-EGFR *** SUMMARY Eleven patients with initially RAS-mutated mCRC were followed from diagnosis to May *** the time of cell-free DNA determination,five patients had undergone one CT line,five patients had undergone two CT lines,and one patient had undergone three CT lines(all in combination with bevacizumab).At the second and third treatment lines[second line(2L),third line(3L)],patients with neo-RAS wt received a combination of CT and *** neo-RAS wt patients treated with anti-EGFR,our findings indicated an increase in progression-free survival for both 2L and 3L(14.5 mo,P=0.119 and 3.9 mo,P=0.882,respectively).Regarding 2L overall survival,we registered a slight increase in neo-RAS wt patients treated with anti-EGFR(33.6 mo vs 32.4 mo,P=0.385).At data cut-off,two patients were still alive:A RAS-mutated patient undergoing 3L treatment and a neo-RAS wt patient who received 2L treatment with anti-EGFR(ongoing).CONCLUSION Our case series demonstrated that monitoring RAS mutations in mCRC by liquid biopsy may provide an additional treatment line for neo-RAS wt patients.

关键词： Metastatic colorectal cancer Rat sarcoma virus mutational status Liquid biopsy Rat sarcoma virus wild-type Neo-rat sarcoma virus wild-type Anti-epidermal growth factor receptor therapy Case report

The centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMn_(6)Ga_(6)S_(16)(Ae=Ca,Sr)

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Science China Chemistry 2024年第9期67卷 2941-2948页

作者： Yang-Ping Zhang Shao-Min Pei Wen-fa Chen Bin-Wen Liu Xiao-Ming Jiang Guo-Cong Guo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China

Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)***,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh *** this work,two isomorphic sulfides AeMn_(6)Ga_(6)S_(16)(Ae=Ca,1;Sr,2)are afforded by modifying the skeleton of centrosymmetric(CS)Mn_(2)Ga_(2)S_(5) via introducing strong electropositive alkaline-earth ***,the incorporation of Ca^(2+)/Sr^(2+)cations allows the elementary[MnGaS_(9)]_(∞)chains to reconfigure into bumpy[MnS_(6)]-[GaS_(4)]layers in a new engagement manner,thus enabling the conversion from CS to NCS *** modifications cause not only strong second-harmonic generation(SHG)responses(~1.5×benchmark AgGaS_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)S_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGaS_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of CS to NCS structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

Y–Z deformable magnetic ring for the treatment of rectal stricture: A case report and review of literature

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World Journal of Gastroenterology 2024年第6期30卷 599-606页

作者： Miao-Miao Zhang Huan-Chen Sha Yuan-fa Qin Yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Treatment of postoperative anastomotic stenosis for colorectal cancer is often challenging,especially for patients who do not respond well to *** cases where patients have undergone an enterostomy,the stenosis can be easily resolved through magnetic ***,common magnetic compre-ssion techniques cannot be performed on those without *** design-ed a novel Y–Z deformable magnetic ring(Y–Z DMR)and successfully applied it to a patient with a stenosis rectal anastomosis and without enterostomy after rectal cancer *** SUMMARY We here report the case of a 57-year-old woman who had undergone a laparo-scopic radical rectum resection(Dixon)for rectal ***,she started facing difficulty in defecation 6 months after *** colonoscopy indicated stenosis of the rectal *** balloon dilation was performed six times on ***,the stenosis still showed a trend of gradual *** the patient did not undergo an enterostomy,the conventional endoscopic magnetic compression technique could not be ***,we imple-mented a Y–Z DMR implemented through the anus under single *** magnetic ring fell off nine days after the operation and the rectal stenosis was *** patient was followed up for six months and reported good *** The Y–Z DMR deformable magnetic ring is an excellent treatment strategy for patients with rectal stenosis and without enterostomy.

关键词： Anastomotic stenosis Colorectal cancer Magnetosurgery Magnetic compression technique Magnetic surgery clinic Case report

Calibration and experimental verification of discrete element parameters of Panax notoginseng root

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 13-23页

作者： Kaiting Xie Zhaoguo Zhang fa’an Wang Xiaolan Yu Chenglin Wang Shifei Jiang faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500China faculty of Modern Agricultural Engineering Kunming University of Science and TechnologyKunming 650500China Guizhou Agricultural Machinery Technology Promotion Station Guiyang 550003China Yunnan Tobacco Machinery Co. LtdKunming 650100China

Existing discrete element method-based simulation analysis of Panax notoginseng root soil separation still has the challenge to get the accurate and reliable basic parameters,which are necessary for discrete element *** this paper,the *** roots suitable for harvesting period were taken as the experimental *** using 3D scanning reverse modeling technology and EDEM software to establish the discrete element model of ***,based on which,the physical and virtual tests were carried out to calibrate the simulation ***,the basic physical parameters(density,triaxial geometric size,moisture content,shear modulus,and elastic modulus)and contact coefficients(static friction coefficient,rolling friction coefficient,and crash recovery coefficient between *** roots and 65Mn steel)were measured by physical ***,treating the contact coefficients of *** roots as the influence factor,the steepest uphill test,and four factors combing five levels of rotational virtual simulation are *** measured relative error accumulation angle and simulation accumulation angle are set as the performance *** results show that the static friction coefficient,rolling friction coefficient,crash recovery coefficient,and surface energy coefficient of *** roots are 0.55,0.35,0.16,and 19.5 J/m2,*** calibration results as parameters of the vibration separation simulation test of *** soil,the Box-Behnken vibration separation simulation tests were carried out,in which the vibration frequency,inclination angle,and vibration amplitude of separation device as factors,screening rate and damage rate of *** soil complex are regarded as *** results show that the optimal operating parameters of the separation device are the vibration frequency of 10 Hz,the inclination angle of 5°,and the amplitude of 6 *** on the optimal operation parameters,the discrete element

关键词： Panax notoginseng root EDEM parameter calibration separation test

The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar Basin,NW China

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Petroleum Science 2024年第2期21卷 836-854页

作者： Mao-Guo Hou Ming Zha Hua Liu Hai-Lei Liu Jiang-Xiu Qu Ablimit Imin Xiu-Jian Ding Zhong-fa Jiang School of Geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and Development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The Fengcheng formation

Upcycling of Poly(butylene adipate-co-terephthalate)into Dual Covalent Adaptable Networks through Chain Breaking-Crosslinking Strategy

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Chinese Journal of Polymer Science 2024年第10期42卷 1505-1513,I0011页

作者： Bin-Bo Wang Rong Huang Xin Wang Tao Jiang Yi Wang Shuai Du fa-Lin Li Jin Zhu Song-Qi Ma Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi214122China Key Laboratory of Bio-based Polymeric Materials Technology and Application of Zhejiang Province Divisions of Polymers and CompositesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China University of Chinese Academy of Sciences Beijing100049China

Poly(butylene adipate-co-terephthalate)(PBAT),a widely studied biodegradable material,has not effectively addressed the problem of plastic *** into consideration the cost-effectiveness,upcycling PBAT should take precedence over direct composting *** present work adopts a chain breaking-crosslinking strategy,upcycling PBAT into dual covalent adaptable networks(CANs).During the chainbreaking stage,the ammonolysis between PBAT and polyethyleneimine(PEI)established the primary crosslinked ***,styrene maleic anhydride copolymer(SMA)reacted with the hydroxyl group,culminating in the formation of dual covalent adaptable *** contrast to PBAT,the PBAT-dual-CANs exhibited a notable Young's modulus of 239 MPa,alongside an inherent resistance to creep and *** to catalysis from neighboring carboxyl group and excess hydroxyl groups,the PBAT-dual-CANs exhibited fast stress ***,they could be recycled through extrusion and hot-press reprocessing,while retaining their *** straightforward strategy offers a solution for dealing with plastic waste.

关键词： Poly(butylene adipate-co-terephthalate) Dynamic crosslinked networks Chain breaking-crosslinking strategy Upcycle Recycle

A novel fused bi-macrocyclic host for sensitive detection of Cr_(2)O_(7)^(2-)based on enrichment effect

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Chinese Chemical Letters 2024年第7期35卷 291-295页

作者： Ting-Ting Huang Jin-fa Chen Juan Liu Tai-Bao Wei Hong Yao Bingbing Shi Qi Lin Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China Key Laboratory of Environment-Friendly Composite Materials of the State Ethnic Affairs Commission Gansu Provincial Biomass Function Composites Engineering Research CenterCollege of Chemical EngineeringNorthwest Minzu University(Northwest University for Nationalities)Lanzhou 730000China

Improving the highly selective and sensitive binding of chemosensor to target guest is always very *** order to solve this issue,herein,the enrichment effect was introduced into the design of chemosensor molecule.A novel bi-fused-macrocyclic host molecule BPN1 was synthesized by bridging a pillar[5]arene and a naphthalene diimide(NDI)group through hydrogen-bond-rich *** the BPN1,the naphthalimide side ring is outside the cavity of the pillar[5]*** addition,Cr(VI)greatly threat human health and the environment due to its severe toxicity,and it is very important to develop effective chemosensor for sensitive and selective detection of Cr_(2)O_(7)^(2-)or its ion *** this paper,the novel bi-fused-macrocyclic host molecule BPN1 can recognize Cr_(2)O_(7)^(2-)with high selectivity and *** mechanism of BPN1 recognition of Cr_(2)O_(7)^(2-)was studied through experiments and density functional theory(DFT),the results show that BPN1 could supply enrichment effect to bind Cr_(2)O_(7)^(2-)through multiple weak interactions such as hydrogen bonds and anion-π,and achieve highly sensitive and selective detection of Cr_(2)O_(7)^(2-).It is a significant and feasible strategy for improve high selectivity and sensitivity of host to specific objects by using the enrichment effect of fused bi-macrocyclic.

关键词： Pillararene Bi-macrocyclic Detection of Cr_(2)O_(7)^(2−) DFT The enrichment effect