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Journal of Environmental Sciences 2006年第5期18卷 1000-1003页

作者： kang cai-yan JIANG Zhi-liang XI Dan-li HE Xing-cun College of Environmental Science and Engineering Donghua University Shanghai 200051 China Department of Material and Chemical Engineering Guilin University of Technology Guilin 541004 China School of Environmental Science and Resource Guangxi Normal University Guilin 541004 China

A new resonance scattering method was proposed for the determination of chlorite, basing on the resonance scattering effect of rhodamine dye. In HCl-sodium acetate buffer solution, chlorite oxidizes 1- into 12 and the reaction of 12 and excess 1- results in If. It is respectively combined with rhodaminc dyes, including rhodamine B （RhB）, butyl rhodamine B （b-RhB）, rhodamine G （RhG） and rhodamine S （RhS）, to form association complex particles, which exhibit stronger resonance scattering （RS） effect at 400 nm. The chlorite concentration of ClO2 in the range of 0.00726-0.218 μg/ml, 0.0102-0.292 μg/ml, 0.00726-0.145 μg/ml and 0.0290- 0.174 μg/ml is respectively linear to the RS intensity of association complex particle systems at 400 nm for the RhB, b-RhB, RhG and RhS. The detection limits of the four systems were respectively 0.00436, 0.00652, 0.00580 and 0.01450μg/ml ClO2^-. In the four systems, the RhB system possesses good stability and high sensitivity. It has been applied to the analysis of chlorite in wastewater with satisfactory results.

关键词： chlorite rhodamine dye association complex particles resonance scattering effect

Laser-assisted grinding of RB-SiC composites:Laser ablation behavior and mechanism

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Chinese Journal of Aeronautics 2024年第1期37卷 362-376页

作者： Zhigang DONG Wenchao SUN Xintong cai Feng yanG yan BAO Renke kang Dongjiang WU Guangyi MA Fangyong NIU Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education School of Mechanical EngineeringDalian University of TechnologyDalian 116024China

Laser ablation is an important process during Laser-Assisted Grinding(LAG)of hard and brittle *** realize controllable material removal during laser ablation of RB-SiC composites,ablation experiments under different Laser Energy Density(LAED)and LAG experiments are *** rules and mechanism of physical phase,ablation morphology and crack characteristics caused by laser irradiation are *** forces of LAG and Conventional Grinding(CG)are *** results show that ablation surface changes from slight oxidation to obvious material removal with LAED increasing,and ablation depth increases *** ablation products change from submicron SiO_(2)particles to nanoscale particles and *** LAED promotes SiC decomposition and sublimation,which leads to the increase of C *** SiC phase forms corrugated shape in recast layer and columnar shape in Heat Affected Zone(HAZ)at 56 J/mm^(2).The cold and heat cycle leads to formation of fishbone *** ablation specimen under 30 J/mm^(2),the grinding force can be reduced by a maximum of 39%and brittle damage region is *** material removal and microcrack generated will significantly reduce the hardness and improve machinability,which can promote grinding efficiency.

关键词： RB-SiC Laser Ceramic Composites Grinding

Assessing the conservation impact of Chinese indigenous chicken populations between ex-situ and in-situ using genome-wide SNPs

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Journal of Integrative Agriculture 2024年第3期23卷 975-987页

作者： Wenting Li Chaoqun Gao Zhao cai Sensen yan yanru Lei Mengya Wei Guirong Sun Yadong Tian Kejun Wang Xiangtao kang College of Animal Science and Technology Henan Agricultural UniversityZhengzhou 450002China The Shennong Laboratory Zhengzhou 450002China

Conservation programs require rigorous evaluation to ensure the preservation of genetic diversity and viability of conservation populations. In this study, we conducted a comparative analysis of two indigenous Chinese chicken breeds, Gushi and Xichuan black-bone, using whole-genome SNPs to understand their genetic diversity, track changes over time and population structure. The breeds were divided into five conservation populations(GS1, 2010, ex-situ;GS2, 2019, ex-situ;GS3, 2019, in-situ;XB1, 2010, in-situ;and XB2, 2019, in-situ) based on conservation methods and generations. The genetic diversity indices of three conservation populations of Gushi chicken showed consistent trends, with the GS3 population under in-situ strategy having the highest diversity and GS2 under ex-situ strategy having the lowest. The degree of inbreeding of GS2 was higher than that of GS1 and GS3. Conserved populations of Xichuan black-bone chicken showed no obvious changes in genetic diversity between XB1 and XB2. In terms of population structure, the GS3 population were stratified relative to GS1 and GS2. According to the conservation priority, GS3 had the highest contribution to the total gene and allelic diversity in GS breed, whereas the contribution of XB1 and XB2 were similar. We also observed that the genetic diversity of GS2 was lower than GS3, which were from the same generation but under different conservation programs(in-situ and ex-situ). While XB1 and XB2 had similar levels of genetic diversity. Overall, our findings suggested that the conservation programs performed in ex-situ could slow down the occurrence of inbreeding events, but could not entirely prevent the loss of genetic diversity when the conserved population size was small, while in-situ conservation populations with large population size could maintain a relative high level of genetic diversity.

关键词： genome-wide SNPs conservation genetic diversity ex-situ in-situ

Numerical modeling of fracture propagation of supercritical CO_(2)compound fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2607-2628页

作者： Hao Chen Yong kang Wanchun Jin Changhai Li Can cai School of Mechanical Engineering Southwest Petroleum UniversityChengdu610500China Laboratory of High-pressure Jet Theory and Application Technology Southwest Petroleum UniversityChengdu610500China Hubei Key Laboratory of Waterjet Theory and New Technology Wuhan UniversityWuhan430072China Sinopec International Petroleum Exploration and Production Corporation Beijing 100029China

The exploitation of shale gas is promising due to depletion of the conventional energy and intensification of the greenhouse *** this paper,we proposed a heat-fluid-solid coupling damage model of supercritical CO_(2)(SC-CO_(2))compound fracturing which is expected to be an efficient and environmentally friendly way to develop shale *** coupling model is solved by the finite element method,and the results are in good agreement with the analytical solutions and fracturing *** on this model,the fracture propagation characteristics at the two stages of compound fracturing are studied and the influence of pressurization rate,in situ stress,bedding angle,and other factors are *** results show that at the SC-CO_(2)fracturing stage,a lower pressurization rate is conducive to formation of the branches around main fractures,while a higher pressurization rate inhibits formation of the branches around main fractures and promotes formation of the main *** bedding and in situ stress play a dominant role in the fracture *** the in situ stress ratio(δ_(x)/δ_(y))is 1,the presence of bedding can reduce the initiation pressure and failure ***,it will cause the fracture to propagate along the bedding direction,reducing the fracture *** rocks without bedding,hydraulic fracturing has the lengthening and widening effects for SC-CO_(2)induced *** shale,fractures induced at the hydraulic fracturing stage are more likely to be dominated by in situ stresses and have a shorter reorientation ***,fracture branches propagating along the maximum principal stress direction may be generated around the main fractures induced by SC-CO_(2)at the hydraulic fracturing *** the branches converge with the main fractures,fracture zones are easily formed,and thus the fracture complexity and damage area can be significantly *** results are instructive for the design and application of SC

关键词： Compound fracturing Fracture propagation Finite element method Damage evolution

Molecular recognition of cyclophanes in water

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Chinese Chemical Letters 2024年第5期35卷 32-44页

作者： Fang-Yuan Chen Wen-Chao Geng kang cai Dong-Sheng Guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China College of Chemistry Nankai UniversityTianjin 300071China

Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular *** mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular *** the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition *** them,cyclophanes represent an important family of macrocyclic receptors that have been extensively *** aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous *** by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous *** review provides an overview of cyclophane receptors designed to bind organic guests in *** categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and *** review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.

关键词： Biomimetic receptor Cyclophane Molecular recognition Hydrophobic effect High-affinity Macrocycles

A Hybrid Level Set Optimization Design Method of Functionally Graded Cellular Structures Considering Connectivity

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Computers, Materials & Continua 2024年第4期79卷 1-18页

作者： yan Dong kang Zhao Liang Gao Hao Li The State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China Institute of Systems Engineering China Academy of Engineering PhysicsMianyang621900China

With the continuous advancement in topology optimization and additive manufacturing(AM)technology,the capability to fabricate functionally graded materials and intricate cellular structures with spatially varying microstructures has grown ***,a critical challenge is encountered in the design of these structures–the absence of robust interface connections between adjacent microstructures,potentially resulting in diminished efficiency or macroscopic failure.A Hybrid Level Set Method(HLSM)is proposed,specifically designed to enhance connectivity among non-uniform microstructures,contributing to the design of functionally graded cellular *** HLSM introduces a pioneering algorithm for effectively blending heterogeneous microstructure ***,an interpolation algorithm is presented to construct transition microstructures seamlessly connected on both ***,the algorithm enables the morphing of non-uniform unit cells to seamlessly adapt to interconnected adjacent *** method,seamlessly integrated into a multi-scale topology optimization framework using the level set method,exhibits its efficacy through numerical examples,showcasing its prowess in optimizing 2D and 3D functionally graded materials(FGM)and multi-scale topology *** essence,the pressing issue of interface connections in complex structure design is not only addressed but also a robust methodology is introduced,substantiated by numerical evidence,advancing optimization capabilities in the realm of functionally graded materials and cellular structures.

关键词： Hybrid level set method functionally graded cellular structure connectivity interpolated transition optimization design

Decoding aging:examining the non-evolutionary event from an evolutionary perspective

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Science China(Life Sciences) 2024年第9期67卷 2026-2029页

作者： yannan Guo kang Xu Jianping cai Zhao Wang Protein Science Key Laboratory of the Ministry of Education School of Pharmaceutical SciencesTsinghua UniversityBeijing 100084China Beijing Institute of Geriatrics Beijing HospitalNational Center of GerontologyNational Health CommissionBeijing 100730China

In an era marked by increased longevity,a deeper understanding of the older population is *** introducing an overlooked evolutionary perspective on aging,this article challenges traditional biogerontology,which primarily focuses on biological and clinical *** articulately differentiates between chronological and physiological aging,suggesting that aging is an evolutionary byproduct rather than a direct evolutionary event.

关键词： aging primarily evolutionary

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罗丹明B荧光猝灭法测定水中痕量亚氯酸根

光谱学与光谱分析 2007年第2期27卷 339-341页

作者：康彩艳蒋治良奚旦立东华大学环境科学与工程学院广西师范大学环境与资源学院广西桂林541004 广西师范大学环境与资源学院桂林工学院材料与化学工程系广西桂林541004

在有KI存在的乙酸钠-HCl酸性缓冲溶液中,用520nm光激发罗丹明B(RhB),在580nm处有一个荧光峰。当有亚氯酸根(ClO_2^-)存在时,罗丹明B荧光峰发生猝灭。亚氯酸根浓度在0.0218~0.51μ***-1范围内与荧光猝灭强度成线性关系,据此建立了一个简... 详细信息

在有KI存在的乙酸钠-HCl酸性缓冲溶液中,用520nm光激发罗丹明B(RhB),在580nm处有一个荧光峰。当有亚氯酸根(ClO_2^-)存在时,罗丹明B荧光峰发生猝灭。亚氯酸根浓度在0.0218~0.51μ***-1范围内与荧光猝灭强度成线性关系,据此建立了一个简便灵敏的亚氯酸根荧光分析新方法,用于测定合成水样中(ClO_2^-)的分析,结果令人满意。

关键词： CIO2^- 罗丹明B 荧光猝灭

Rapid prediction of flow and concentration fields in solid-liquid suspensions of slurry electrolysis tanks

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2006-2016页

作者： Tingting Lu kang Li Hongliang Zhao Wei Wang Zhenhao Zhou Xiaoyi cai Fengqin Liu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Intelligent Optimized Manufacturing in Mining&Metallurgy Process Beijing 102628China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Slurry electrolysis(SE),as a hydrometallurgical process,has the characteristic of a multitank series connection,which leads to various stirring conditions and a complex solid suspension *** computational fluid dynamics(CFD),which requires high computing resources,and a combination with machine learning was proposed to construct a rapid prediction model for the liquid flow and solid concentration fields in a SE *** scientific selection of calculation samples via orthogonal experiments,a comprehensive dataset covering a wide range of conditions was established while effectively reducing the number of simulations and providing reasonable weights for each ***,a prediction model of the SE tank was constructed using the K-nearest neighbor *** results show that with the increase in levels of orthogonal experiments,the prediction accuracy of the model improved *** model established with four factors and nine levels can accurately predict the flow and concentration fields,and the regression coefficients of average velocity and solid concentration were 0.926 and 0.937,*** with traditional CFD,the response time of field information prediction in this model was reduced from 75 h to 20 s,which solves the problem of serious lag in CFD applied alone to actual production and meets real-time production control requirements.

关键词： slurry electrolysis solid-liquid suspension computational fluid dynamics K-nearest neighbor algorithm rapid prediction

Acarbose glycosylation by AcbE for the production of acarstatins with enhancedα-amylase inhibitory activity

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Synthetic and Systems Biotechnology 2024年第2期9卷 359-368页

作者： Xin Zhang Qungang Huang Ziyue Guo Feifei cai Qianjin kang Linquan Bai State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai200240China College of Life Science Tarim UniversityAlar843300China

Acarbose is a potent glycosidase inhibitor widely used in the clinical treatment of type 2 diabetes mellitus(T2DM).Various acarbose analogs have been identified while exploring compounds with improved pharmacological *** this study,we found that AcbE from Actinoplanes ***50/110 catalyzes the production of acarbose analogs that exhibit significantly improved inhibitory activity towardsα-amylase than *** AcbE mainly catalyzed the formation of two new compounds,namely acarstatins A and B,using acarbose as *** high-resolution mass spectrometry,nuclear magnetic resonance,and glycosidase hydrolysis,we elucidated their chemical structures as O-α-d-maltosyl-(1→4)-acarbose and O-α-d-maltotriosyl-(1→4)-acarbose,*** A and B exhibited 1584-and 1478-fold greater inhibitory activity towards human salivaryα-amylase than ***,both acarstatins A and B exhibited complete resistance to microbiome-derived acarbose kinase 1-mediated phosphorylation and partial resistance to acarbose-preferred glucosidase-mediated ***,acarstatins A and B have great potential as candidate therapeutic agents for T2DM.

关键词： Acarbose analogs α-amylase inhibitory activity Actinoplanes sp. Transglycosylase