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工程建设与设计 2024年第13期 126-128页

作者：李行利中铁十一局集团第四工程有限公司武汉430061

利用FLAC 3D数值模拟程序,对城仔山隧道进行了机械化三台阶法施工数值模拟,发现上中、下、台阶开挖后,拱顶持续下沉,而仰拱开挖后,拱顶位移基本不变,且掌子面围岩剪应变增量最大值未形成潜在的连续剪切破坏面,故掌子面未发生整体破坏。

关键词：隧道开挖三台阶施工数值模拟 FLAC 3D

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Cloning and molecular characterization of△^(12)-fatty acid desaturase gene from Mortierella isabellina

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World Journal of Gastroenterology 2006年第21期12卷 3373-3379页

作者： Ming-Chun li hang li Dong-Sheng Wei Lai-Jun Xing Department of Microbiology The College of Life Science Nankai University Tianjin 30071 China

AIM： To clone △^12 -fatty acid desaturase gene of Mortierella isabellina and to functionally characterize this gene in vitro and in ***： Reverse transcriptional polymerase chain reaction （RT-PCR） was used to clone the open reading frame of △^12-fatty acid desaturase gene （D12D） of Mortierella isabellina. Plasmids pEMICL12 and pYMICL12 were constructed with it. pEMICL12 was transformed into Escherichia coli（***） strain BL21 using CaCl2 method for expression after induction with IPTG. pTMICL12 was transformed into Saccharomyces cerevisiae strain IN- VSc1 using lithium acetate method for expression under the induction of galactose. Northern blotting method was used to investigate the effect of temperature on the transcriptional level of this gene in *** strain IN- ***： Recombinant plasmids pEMICL12 and pTMICL12 were successfully constructed and transformed into E. coli and *** separately with appropriate method. After induction with IPTG and galactose, it was found that expression of △^12-fatty acid desaturase genes in *** and S. cerevisiae under appropriate conditions led to the production of active △^12-fatty acid desaturase, which could convert 17.876% and 17.604% of oleic acid respectively to linoleic acid by GC-MS detection in vitro and in ***： Cloning and expression of *** D12D gene in *** and *** is successfully completed.

关键词： Mortierella isabellina △^12-fatty acid desaturase In vitro expression

Transcriptome Analysis of Heterosis in Survival in the Hybrid Progenies of‘Haida No.1’and Orange-Shelled lines of the Pacific Oyster Crassostrea gigas

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Journal of Ocean University of China 2024年第1期23卷 199-208页

作者： YANG hang li Qi Key Laboratory of Mariculture Ministry of EducationOcean University of ChinaQingdao 266003China

Heterosis has been exploited to enhance the yield and adaptability in various shellfish species;however,the molecular basis of it remains *** Pacific oyster Crassostrea gigas is one of the most economically important aquaculture species,and its productive traits can be improved by ***,an intraspecific cross between orange shell(O,10th generation)and‘Haida No.1’(H,13th generation)of *** was performed to assess the heterosis of survival *** rates of hybrid family(OH)and inbred families(HH and OO)were compared at larval stage,and eyed-pediveliger larvae of three families were subjected to transcriptome *** analysis results of best-parent heterosis and mid-parent heterosis showed that the hybrid family exhi-bited a high heterosis in survival relative to the parental *** OH-M(OH ***)and OH-P(OH ***)had 425 and 512 dif-ferentially expressed genes(DEGs),*** enrichment analysis of these DEGs revealed that the significantly enrich-ed genes function in virion binding,C-type lectin receptor signaling pathway,cellular defense response and other immune-related pro-cesses,which involves perlucin-like protein,CD209 antigen-like protein,ZNFX1,caspase-3 and acan *** differentially ex-pressed genes in OH-M and OH-P,together with the immune-related processes mentioned above may play an important role in the larval survival of *** addition,three genes(CYP450,fucolectin and perlucin-like)are associated with the orange shell and low survival of maternal oyster *** findings provide support for the application of hybrid with superior survival and will facilitate the understanding of heterosis formation in the Pacific oyster.

关键词： Crassostrea gigas survival rate heterosis transcriptome

Effect of Cr_(2)O_(3) on properties of CaO-SiO_(2)-Fe_(t)O-MgO system and dissolution behavior of lime

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Journal of Iron and Steel Research International 2024年第4期31卷 870-881页

作者： Shan-nan li Jian-li li Yue Yu hang-yu Zhu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The productivity of the chrome-containing semi-steel converter smelting process is directly affected by the slag-forming speed during the converter preliminary *** effects of Cr_(2)O_(3) content on the physicochemical properties of the CaO-SiO_(2)-Fe_(t)O-MgO system,such as melting temperature,solidification behavior,mineral composition,and lime dissolution rate,were *** results showed that the slag was an amorphous phase at 1500℃.When Cr_(2)O_(3) was added,Ca(Fe,Mg)Si_(2)O_(6) and spinel were formed in the *** the increase in Cr_(2)O_(3) content,the amount of spinel precipitation increased,and the dendritic FegO_(4) crystal gradually changed into the granular(Fe,Mg)(Fe,Cr)2O_(4) *** the Cr_(2)O_(3) content increased from O to 2.91 wt.%,the melting temperature of the slag rose,and the melting range of the slag expanded slightly,but the lime dissolution rate did not *** the Cr_(2)O_(3) content further increased to 9.09 wt.%,the melting temperature continued to rise,the melting range rapidly expanded,and the lime dissolution rate decreased.

关键词： Cr_(2)O_(3) Vanadium-titanium magnetite Converter Slag lime dissolution

Rhodium-catalyzed addition reactions of benzylic C–H bonds to cyclic N-sulfonyl ketimines viaπ-coordination

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Chinese Chemical Letters 2024年第3期35卷 287-291页

作者： Yuntong li hang Shi Department of Chemistry Zhejiang UniversityHangzhou 310027China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and ***,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic *** this study,we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–H bonds to cyclic N-sulfonyl ketamines throughπ-*** strategy enables the synthesis of a diverse range of N-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.

关键词： Benzylic deprotonation Cyclic N–sulfonyl ketimines π-Coordination Mannich-type addition Rhodium catalysis

Highly efficient and stable 2D/3D perovskite solar cells based on surface reconstruction and energy level alignment

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Science China Chemistry 2024年第9期67卷 3083-3090页

作者： Qiaohui li hang liu Tong Zhou Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science and TechnologyQingdao 266042China The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

Realizing simultaneous adjustment of energy levels and work functions in two-dimensional/three-dimensional(2D/3D)perovskite solar cells(PSCs)is a ***,a pseudohalide 3,5-bis(trifluoromethyl)benzylammonium tetrafluoroborate(TFPMABF_(4))was used to react with unreacted Pb I2on the surface of 3D bulky perovskite to form a mixed halide of 2D perovskite denoted(TF-PMA)_(2)FA_(2)Pb_(3)I_(8)(BF_(4))_(2).This novel 2D/3D perovskite enables the simultaneous adjustment of energy levels and work functions on the surface of active *** to the significantly enhanced quality of 2D/3D perovskite film,decreased surface defects and increased charge carrier lifetime,the 2D/3D PSCs exhibit an outstanding power conversion efficiency(PCE)of 25.15%and a high V_(OC)of 1.194 ***,2D/3D PSCs exhibit remarkable enhancements in environmental stability,unencapsulated devices retaining more than 90%of their initial PCE at 50%humidity for 2,280 h.

关键词： 2D/3D perovskite perovskite solar cells organic spacers energy levels alignment

Controllable CPL response driven by achiral UV-photosensitive dichroic dye through cholesteric liquid crystals

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Science China Chemistry 2024年第4期67卷 1250-1255页

作者： Yihan Chen Yang li hang li Lulu li Yiwu Quan Yixiang Cheng State Key Laboratory of Analytical Chemistry for life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of High-Performance Polymer Material and Technology of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Versatile stimuli-responsive circularly polarized luminescent(CPL)materials have potential applications in information storage,security encryption,and intelligent *** this study,the Z/E isomerization of ultraviolet(UV)-photosensitive achiralα-cyanostilbene derivative was used as an achiral dichroic dye(Switch)to drive the controllable CPL-active response in cholesteric liquid crystals(CLCs).Under irradiation by 365 nm UV light,the resulting CLCs-Z-Switch underwent a Z-to-E configuration isomerization as CLCs-E-Switch,accompanied by a decrease in its dichroic order parameter(SFvalue)from 0.15to *** the quantum yield(QY)of CLCs-E-Switch increased from 8.1%(CLCs-Z-Switch)to 16.8%,the corresponding glumvalues of CPL emission decreased from+0.55/-0.57 to+0.37/-0.39 due to a decrease in the order of helical arrangement of E-Switch in E7 *** study enables photosensitive CLCs-Switch to be applied for optical information storage devices.

关键词： circularly polarized luminescent photosensitive dichroic dye cholesteric liquid crystals chiral induction

Price Masking Strategy of Cross-Border E-Commerce Platform Financing

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Journal of Systems Science & Complexity 2024年第2期37卷 668-691页

作者： li Jianbin hang Zhouxin CHEN Zhiyuan XIAO Shan School of Management Huazhong University of Science and TechnologyWuhan 430074China School of Economics and Management Wuhan UniversityWuhan 430072China

E-commerce platform financing is a new service pattern of supply chain ***,this pattern may bring some new issues when considering the problem of cash flow shortage and financing difficulties of small and medium-sized *** enterprises use this service,they worry about the leakage of preferential wholesale price when applying the full loan amount and providing the true transaction *** on the model consisting of a supplier,a retailer and a cross-border e-commerce platform,the authors design a price masking strategy to prevent the retailer’s preferential wholesale price information from *** authors analyze the profit of the retailer and the platform before and after adopting the price masking *** authors find that the price masking strategy always benefits the ***,the optimal profit of the retailer and the platform are both affected by the loan interest ***,there exists a range of loan interest rates that can benefit both the retailer and the platform if the price masking strategy is *** research emphasizes that platform can expand the total business volume by allowing retailers to use price masking *** other words,there will be more and more retailers attracted by the strategy,which benefits the long-term growth of cross-border e-commerce platform financing.

关键词： Cross-border e-commerce e-commerce platform financing price masking supply chain finance

Collision-free parking recommendation based on multi-agent reinforcement learning in vehicular crowdsensing

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Digital Communications and Networks 2024年第3期10卷 609-619页

作者： Xin li Xinghua Lei Xiuwen liu hang Xiao College of Computer Science and Technology China University of Petroleum(East China)QingDao266580China

The recent proliferation of Fifth-Generation(5G)networks and Sixth-Generation(6G)networks has given rise to Vehicular Crowd Sensing(VCS)systems which solve parking collisions by effectively incentivizing vehicle ***,instead of being an isolated module,the incentive mechanism usually interacts with other *** on this,we capture this synergy and propose a Collision-free Parking Recommendation(CPR),a novel VCS system framework that integrates an incentive mechanism,a non-cooperative VCS game,and a multi-agent reinforcement learning algorithm,to derive an optimal parking strategy in real ***,we utilize an LSTM method to predict parking areas roughly for recommendations *** incentive mechanism is designed to motivate vehicle participation by considering dynamically priced parking tasks and social network *** order to cope with stochastic parking collisions,its non-cooperative VCS game further analyzes the uncertain interactions between vehicles in parking *** its multi-agent reinforcement learning algorithm models the VCS campaign as a multi-agent Markov decision process that not only derives the optimal collision-free parking strategy for each vehicle independently,but also proves that the optimal parking strategy for each vehicle is ***,numerical results demonstrate that CPR can accomplish parking tasks at a 99.7%accuracy compared with other baselines,efficiently recommending parking spaces.

关键词： Incentive mechanism Non-cooperative VCS game Multi-agent reinforcement learning Collision-free parking strategy Vehicular crowdsensing

Image Segmentation-P300 Selector: A Brain–Computer Interface System for Target Selection

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Computers, Materials & Continua 2024年第5期79卷 2505-2522页

作者： hang Sun Changsheng li He Zhang Mechanical Engineering Nanjing University of Science and TechnologyNanjing210018China

Brain–computer interface (BCI) systems, such as the P300 speller, enable patients to express intentions withoutnecessitating extensive ***, the complexity of operational instructions and the slow pace of characterspelling pose challenges for some patients. In this paper, an image segmentation P300 selector based on YOLOv7-mask and DeepSORT is proposed. The proposed system utilizes a camera to capture real-world objects forclassification and tracking. By applying predefined stimulation rules and object-specificmasks, the proposed systemtriggers stimuli associated with the objects displayed on the screen, inducing the generation of P300 signals in thepatient’s brain. Its video processing mechanism enables the system to identify the target the patient is focusing oneven if the object is partially obscured, overlapped, moving, or changing in number. The system alters the target’scolor display, thereby conveying the patient’s intentions to caregivers. The data analysis revealed that the selfrecognitionaccuracy of the subjects using this method was between 92% and 100%, and the cross-subject P300recognition precision was 81.9%–92.1%. This means that simple instructions such as “Do not worry, just focuson what you desire” effectively discerned the patient’s intentions using the Image Segmentation-P300 selector. Thisapproach provides cost-effective support and allows patients with communication difficulties to easily express theirneeds.

关键词： Brain-computer interface deep learning electroencephalogram P300 YOLOv7-mask