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Facile synthesis of the dodecahydridododecaborate (B12H122-) from borane Lewis base adducts

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Science China Chemistry 2025年

作者： Yi Jing xin-Ran Liu xing-Hua Wang Hui Han Sha-Sha Liang xi-Meng Chen Dong-Hui Wei Lai-Sheng Wang Xue-Nian Chen College of Chemistry Zhengzhou University School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced MaterialsHenan Normal University Department of Chemistry Brown University

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy,chemistry,medicine,and materials science because of their unique physical and chemical *** efforts have been made in the past decades to find more effective synthetic methods for this important class of boron ***,existing synthetic methods suffer from low efficiency and low ***,we report a facile one-pot synthesis of[（CH3）3S]2B12H12with moderate yields at mild *** mechanisms for the multi-step chemoselective synthesis of B12H122-without other by-products are elucidated based on theoretical results and our previous *** Lewis base used in B–H bond condensation reaction,which acts as a hydrogen or to balance the newly generated polyhedral borane charges,is proposed and studied in *** current study has led to a more effective and selective synthetic method for B12H122-and has also implicated the syntheses of other new polyhedral boranes.

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朋辈心理咨询进社区:高校“一站式”学生社区心理育人功能实践路径研究

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黑龙江高教研究 2025年第1期43卷 135-139页

作者：邢晓雪王怀勇南京工业大学江苏南京211816 上海师范大学上海200234

结合高校“一站式”学生社区综合管理模式建设提质增效工作指南,探讨朋辈咨询进入学生社区的天然耦合性,并从社会生态系统理论视角提出朋辈咨询嵌入“一站式”学生社区实现心理育人功能的多重路径选择,在微观环境中注重发挥朋辈咨询员... 详细信息

结合高校“一站式”学生社区综合管理模式建设提质增效工作指南,探讨朋辈咨询进入学生社区的天然耦合性,并从社会生态系统理论视角提出朋辈咨询嵌入“一站式”学生社区实现心理育人功能的多重路径选择,在微观环境中注重发挥朋辈咨询员的匹配优势,在中观环境中以朋辈咨询体制为抓手优化社区心理育人体系建设,在宏观环境中利用朋辈咨询资源加强常态化的“文化渗透式”心理健康教育,全方位、立体式、浸润式打通高校心理育人“最后一公里”。

关键词： “一站式”学生社区朋辈咨询心理育人社会生态系统理论

An image encryption algorithm based on improved baker transformation and chaotic S-box

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Chinese Physics B 2021年第6期30卷 216-225页

作者： xing-Yuan Wang huai-huai Sun Hao Gao School of Information Science and Technology Dalian Maritime UniversityDalian 116026China

The algorithm is an image encryption algorithm based on the improved baker transformation and chaotic substitution box(S-box). It mainly uses the initial values and parameters of a one-dimensional logistic chaotic system as an encryption key. Specifically, in the image scrambling stage, the algorithm primarily uses an improved baker transform method to process the image. In the image diffusion stage, the algorithm first uses the chaotic S-box method to process the encryption key. Secondly, an exclusive OR(XOR) operation is performed on the image and the encryption key to initially diffuse the image. Finally, the image is again diffused using the method of ortho XOR. Simulation analysis shows that the algorithm can achieve good encryption effect, simple and easy implementation, and good security. In the digital image communication transmission, it has good practical value.

关键词： image encryption improved baker transformation chaotic S-box chaotic sequence

COUPLING EFFECT BETWEEN RELIABILITY OF BEDDING LAYER AND STABILITY OF DOWNSTREAM CONCRETE SLAB OF OVERFLOW EARTH-ROCK COFFERDAM

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Journal of Hydrodynamics 2007年第5期19卷 613-622页

作者： HU Zhi-gen FAN xi-e huai Wen-xin LIU Quan ZHU Ming-xing State Key Laboratory of Water Resource and Hydropower Engineering Science Wuhan University Wuhan 430072 China China Gezhouba （Group） Corporation Yichang 443002 China

The protection of downstream concrete slab is a key issue for the stability of overflow earth-rock cofferdam. The coupling effect between bedding layer and concrete slab was taken into account when the stability of downstream concrete slab was researched. The characteristics of overflow and seepage over the downstream concrete slab were investigated when floodwater passes over the cofferdam. Firstly a limit equation of seepage failure for the bedding layer was derived with the consideration of geometric and mechanical factors, and a reliability model was established and numerically simulated. Then based on the reliability calculation for the bedding layer, the coupling effect between bedding layer and downstream concrete slab was analyzed. Under the most unfavorable pressure condition for the concrete slab, its instability criterion was put forward, which offers a structural design tool of downstream concrete slab for overflow earth-rock cofferdam. Compared with model tests, it shows that the model of reliability calculation of bedding layer and the stability analysis of downstream concrete slab are effective.

关键词： overflow earth-rock cofferdam couplingeffect reliability calculation stability analysis Monte Carlomethod

On the Products Arising from the Kummer Conjecture

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Acta Mathematica Sinica,English Series 2012年第8期28卷 1677-1688页

作者： Jun huai ZHANG Yuan YI Ping xi Research Center for Basic Science Xi'an Jiaotong University

Let q be a sufficiently large integer and X be a Dirichlet character modulo q. In this paper, we extend the product x（-1）=-1 L（1, X） with prime q, arising from the Kummer conjecture, to the products of some genera... 详细信息

关键词： Kummer conjecture I)irichlet L-function Dirichlet character

Effects of Two Composted Plant Pesticide Residues,Incorporated with Trichoderma viride,on Root-Knot Nematode in Balloonflower

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Agricultural Sciences in China 2009年第4期8卷 447-454页

作者： ZHANG Shuang-xi ZHANG xing Biorational Pesticide R＆D Center Northwest A＆F University Yangling 712100 P.R.China

Plant pesticide residues, such as chinaberry （Melia toosendan） residue and sand cypress （Sabina vulgaris） residue, are pesticidal plant materials discarded after the bioactive ingredient has been extracted with organic solvents. The only option for botanical pesticide residue utilization has been as landfill. Chinaberry residue （CBR） and sand cypress residue （SCR） were collected and composted in Yangling, Shaanxi Province, China. We studied the effects of chinaberry residue compost （CBRC）, CBRC incorporated with Trichoderma viride （CBRCT）, sand cypress residue compost （SCRC）, and SCRC incorporated with T. viride （SCRCv） on the root-knot nematode, Meloidogyne incognita, infesting the balloonflower （Platycodon grandiflorum）. Bioassay results indicated that stock solutions of the CBRCT and SCRCT extracts significantly inhibited egg hatching and caused high larval mortality, followed in degree by the CBRC and SCRC extracts. The CBR and SCR extracts caused very low inhibition of eggs and larvae. Supplementing potting mixtures with these four composts reduced the severity of root galling and increased the proportion of marketable roots. The severity of root galling decreased and the average weight of the marketable roots increased with an increase in all the composts when supplemented at rates from 5 to 30%. CBR- and SCR-supplemented pot soils also inhibited the nematodes, but CBR and SCR applied to the soil had a phytotoxic effect and inhibited balloonflower growth. Supplementing field soil with the composts reduced the severity of root galling and the populations of southern root-knot nematodes in the soil. CBRCT and SCRCT clearly enhanced the average weight of the marketable roots by 30.45 and 26.64%, respectively. Continuous supplementation with CBRCT or SCRCT in the same field significantly enhanced the control of the root-knot nematode, and the populations of nematodes continued to decrease with second inoculations. The populations of total Trichoderma spp. were dis

关键词： balloon flower root-knot nematode plant pesticide residue compost compost extract

Numerical assessment of the erosion risk for cavitating twisted hydrofoil by three methods

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Journal of Hydrodynamics 2021年第4期33卷 698-711页

作者： Ting-ting Lei huai-yu Cheng Bin Ji xiao-xing Peng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China National Key Laboratory on Ship Vibration and Noise China Ship Scientific Research CenterWuxi214082China

In this paper, the large eddy simulation (LES) method in conjunction with the Zwart cavitation model is adopted for the assessment of the erosion risk on a hydrofoil surface. The numerical results are in good agreement with the experiments. On this basis, three methods, namely the intensity function method (IFM), the time-averaged aggressiveness indicators (TAIs) and the gray level method (GLM), are applied for the assessment of the erosion risk. It is shown that the erosion intensity index of the IFM is extremely sensitive to the artificially selected thresholds, which greatly limits the application of the method. The erosion risk predicted by four indicators in the TAIs does not agree well with the experimental results. Further analysis demonstrates that the GLM using the instantaneous pressure field is relatively satisfactory, which can provide a reasonable assessment of the erosion and is not very sensitive to the artificially selected thresholds. To further improve the accuracy of the GLM for the erosion risk prediction, the time-average pressure field is adopted in the GLM for the erosion evaluation. It is suggested that the erosion assessment by using the time-averaged pressure field is in better agreement with the experimental results when compared with that by using the instantaneous pressure field.

关键词： Cavitating flow erosion numerical simulation threshold selection

Selection of Fixed Effects in High-dimensional Generalized Linear Mixed Models

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Acta Mathematica Sinica,English Series 2023年第6期39卷 995-1021页

作者： xi Yun ZHANG Zai xing LI School of Science China University of Mining&Technology(Beijing)Beijing 100083P.R.China

The selection of fixed effects is studied in high-dimensional generalized linear mixed models(HDGLMMs)without parametric distributional assumptions except for some moment *** iterative-proxy-based penalized quasi-likelihood method(IPPQL)is proposed to select the important fixed effects where an iterative proxy matrix of the covariance matrix of the random effects is constructed and the penalized quasi-likelihood is *** establish the model selection consistency with oracle properties even for dimensionality of non-polynomial(NP)order of sample *** studies show that the proposed procedure works ***,a real data is also analyzed.

关键词： Fixed effects selection HDGLMMs penalized quasi-likelihood proxy covariance matrices theoretical properties

Experimental Study on the Viscosity of Soft Cohesive Sediments Around A Vibrating Pillar

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China Ocean Engineering 2022年第2期36卷 289-298页

作者： DONG Chuan-ming YU Guo-liang ZHANG huai-xin ZHANG Min-xi SKLOE CISSESchool of Naval ArchitectureOcean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Navigation College Dalian Maritime UniversityDalian 116026China

Offshore structures are subject to environmental loads such as waves,currents,or wind,which may induce cyclic lateral vibration at the *** cyclic vibration loadings may affect the rheological property of the sediments adjacent to the foundation and the stability of the *** is especially true when the structures are founded on cohesive sedimentary *** this study,the viscosity of soft cohesive sediments adjacent to a vibrating pillar was considered,and as a primary index of the rheological characteristics of the *** investigation was performed using the sinking ball *** experimental findings indicated that the viscosity of cohesive sediments decrease with increase of the liquidity index and vibration intensity.A simple semi-empirical formula was *** structures of the cohesive sediments were destroyed due to the mechanical vibration,and the sediments were fluidized during vibration *** shear strength of the cohesive sediments decreased with increased vibration intensity,not only because of the increased pore water pressure but also the decreased viscosity of cohesive sediments following sediment fluidization.

关键词： cohesive sediment vibration intensity viscosity coefficient fluidization liquidity index