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Chinese Journal of Chemical Engineering 2024年第4期68卷 76-82页

作者： Shaoyun Wu zhuang Ma Zichi Yang Suying Zhao Caijin zhou Huidong Zheng Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou362114China

Micromixing efficiency is an important parameter for evaluating the multiphase mass transfer performance and reaction efficiency of *** this work,the novel curved capillary reactor with different shapes was designed to generate Dean flow,which was used to enhance the liquid-liquid micromixing *** Villermaux-Dushman probe reaction was employed to characterize the micromixing performance in different curved capillary *** effects of experiment parameters such as liquid flow rate,inner diameter,tube length,and curve diameter on micromixing performance were systematically *** the optimal conditions,the minimum value of the segmentation factor XS was *** was worth noting that at the low Reynolds number(Re<30),the change of curved shape on the capillary microreactor can significantly improve the micromixing performance with XS reduced by 37.5%.Further,the correlations of segment index XS with dimensionless factor such as Reynolds number or Dean number were developed,which can be used to predict the liquid-liquid micromixing performance in capillary microreactors.

关键词： Microreactor Process intensification Micromixing performance Dean flow

Vibration suppression for rotating space slender flexible structures based on novel deformation description and NNSMC controller with hyperbolic tangent function

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Chinese Journal of Aeronautics 2024年第10期37卷 339-364页

作者： Dongyang SHANG Xiaopeng LI Men yin Sainan zhou School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

Rotating Space Slender Flexible Structures(RSSFS)are extensively utilized in space operations because of their light weight,mobility,and low energy *** realize the accurate space operation of the RSSFS,it is necessary to establish a precise mechanical model and develop a control algorithm with high ***,with the application of traditional control strategies,the RSSFS often suffers from the chattering phenomenon,which will aggravate structure *** this paper,novel deformation description is put forward to balance modeling accuracy and computational efficiency of the RSSFS,which is better appropriate for real-time ***,the Neural Network Sliding Mode Control(NNSMC)strategy modified by the hyperbolic tangent(tanh)function is put forward to compensate for modeling errors and reduce the chattering phenomenon,thereby improving the trajectory tracking accuracy of the ***,a mathematical model for the RSSFS is developed according to the novel deformation description and the vibration theory of flexible *** of the deformation accuracy between different models proves that the novel modeling method proposed has high modeling ***,the universal approximation property of the Radial Basis Function(RBF)neural network is put forward to determine and compensate for modeling errors,which consist of higher-order modes and the uncertainties of external *** addition,the tanh function is proposed as the reaching law in the conventional NNSMC strategy to suppress driving torque *** control law of modified NNSMC strategy and the adaptive law of weight coefficients are developed according to the Lyapunov theorem to guarantee the RSSFS ***,the simulation and physical experimental tests of the RSSFS with different control strategies are *** results show that the control law according to the novel deformation description and the modified NNSMC strategy can obta

关键词： Space slender flexible structure Novel deformation description RBF neural network Vibration suppression Hyperbolic tangent function

Synthesis　and　Crystal　Structure　of　［Na（DB18C6）（CH_3OH）］_2Mo_6O_（19）·（DB18C6）·（CH_3OH）

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Chinese Journal of Structural Chemistry 1995年第2期14卷 139-144页

作者： zhou yin-zhuang Tu Shu-Jie Jin Xiang-Lin Liu Shun-Cheng(Department of Chemistry, Capital Normal University,Beijing 100037)(Institute of Physical Chemistry, Beijing University,Beijing 100871)(Experimental Center, Capital Normal University, Beijing 10003

The preparation method of [Na ( DB18C6) (CH_3OH )]_2Mo_6O_(19)·(DB18C6)·(CH_3OH) , where DB18C6 is dibenzo-18-crown-6, is described. Thecrystal and molecular structure of the title complex has been determined crystallographically. The title complex crystallizes in the monoclinic system,space group P2_1/c ,a=18. 727(6) ,b=19. 555(6) , c=22. 827(7) ,β=112. 84(3)°, V=7704(4) ￣3 ,M_r = 2102. 9 , Z = 4 , F (000 ) = 4224 , μ= 1 . 028 mm ￣(-1), D_c = 1.813 g/cm￣3 . final R =0. 075 and R_w= 0. 078 based on 4463 observed reflections with F>6. 0σ(F) . The complex consists of [Mo_6O_(19)]￣(2-) ,[Na(DB18C6)]￣+ and CH_3OH, which are linked by long distance interaction through O-Na-O bond.

关键词： synthesis crystal structure crown ether isopoly oxomolybdate

Amino acids in piglet diarrhea:Effects,mechanisms and insights

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Animal Nutrition 2024年第1期16卷 267-274页

作者： Xihong zhou Jing Liang Xia Xiong Yulong yin Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureThe Chinese Academy of SciencesChangsha 410125China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

Piglet diarrhea is among one of the most serious health problems faced by the pig industry,resulting in significant economic *** disease in piglets has a multifactorial etiology that is affected by physiology,environment,and management *** is the most apparent symptom of intestinal *** a key class of essential nutrients in the piglet diet,amino acids confer a variety of beneficial effects on piglets in addition to being used as a substrate for protein synthesis,including maintaining appropriate intestinal integrity,permeability and epithelial renewal,and alleviating morphological damage and inflammatory and oxidative ***,provision of appropriate levels of amino acids could alleviate piglet *** amino acid effects are mediated by metabolites,gut microbes,and related signaling *** this review,we summarize the current understanding of dietary amino acid effects on gut health and diarrhea incidence in piglets,and reveal the mechanisms *** also provide ideas for using amino acid blends and emphasize the importance of amino acid balance in the diet to prevent diarrhea in piglets.

关键词： Piglet Amino acid Diarrhea Gut microbe Immune

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Metal complexes of bipyridine-functionalized covalent organic frameworks as efficient electrocatalysts for oxygen evolution reaction

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Rare Metals 2024年第7期43卷 3096-3106页

作者： zhuang-zhuang Wu Tian Xia ying Liang Yong-Peng Li Zhu-yin Sui Li-Juan Feng Dao-Xiong Wu Xin-Long Tian Qi Chen State Key Laboratory of Marine Resource Utilization in South China Sea School of Marine Science and EngineeringHainan UniversityHaikou 570228China School of Chemistry and Chemical Engineering Yantai UniversityZhuhai519041China School of Bioengineering Zhuhai Campus of Zunyi Medical UniversityZhuhai519041China

Electrocatalytic water splitting is considered a clean and practic al method for producing *** this study,COF-Bpy,a bipyridine-functionalized covalent organic framework(COF),was prepared via post-synthetic modification,after which electrocatalysts for the oxygen evolution reactions(OER)were formed through coordination to single-or double-transition metals(Fe,Co,Ni,FeCo,FeNi or CoNi).COF-Bpy@FeNi delivered the best OER performance among the studied electrocatalysts,with an overpotential of 399 mV at 10 mA·cm^(-2)in an alkaline electrolyte(1.0 mol·L^(-1)KOH aqueous).Notably,the electrocatalytic performance of COF-Bpy@FeNi showed slight degradation during durability testing,which is ascribable to its irreversible benzoquinoline structure and strong metal *** expected,COF-Bpy@FeNi exhibited a low overpotential of 347 mV at a turnover frequency(TOF)of 0.1 s^(-1),which suggests that COF-Bpy@FeNi possesses excellent intrinsic electroc atalytic OER ***,density functional theory(DFT)calculations reveal that the Ni site plays a major role,while the Fe site adjusts the electronic structure of the Ni ions,which rationalizes the excellent OER properties of COF-Bpy@*** study not only provides a simple and efficient method for complexing COFs with transition metals,but also offers a novel strategy for designing porous organic polymer electrocatalysts.

关键词： Covalent organic framework Oxygen evolution reactions(OER)electrocatalyst Nickel-iron synergy Water splitting

Early-diverging Titanosauriform(Dinosauria,Sauropoda)Teeth from the Lower Cretaceous Yixian Formation of Southeastern Inner Mongolia,Northeast China

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 303-310页

作者： ZHANG Honggang yin Yalei PEI Rui zhou Changfu College of Earth Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266570China College of Paleontology Shenyang Normal UniversityShenyang 110034China Key Laboratory of Evolution of Past Life in NE Asia Ministry of Natural ResourcesShenyang 110034China Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China

Three eusauropod teeth(SDUST-V1064,PMOL-AD00176,PMOL-ADt0005)are reported from the Lower Cretaceous Yixian Formation of Ningcheng,southeastern Inner Mongolia,*** of them(SDUST-V1064,PMOL-AD00176)are assigned to early-diverging titanosauriforms in having slightly mesiodistal expansion at the base of the tooth crown,a slenderness index value>2.0 and<4.0,and D-shaped cross ***,SDUST-V1064 and PMOL-AD00176 are referred as an Euhelopus-like titanosauriform on the basis of having a sub-circular boss on the lingual surface and an asymmetrical crown-root margin which slants apically,*** scan data of SDUST-V1064 reveals new dental information of early-diverging titanosauriforms,for example,the enamel on the labial side thicker than that on the lingual side,an enamel/dentine ratio of 0.26 and a boss present on the lingual side of the dentine of the crown.

关键词： teeth Titanosauriformes Lower Cretaceous Yixian Formation Ningcheng

Synthesis and Crystal Structure of Co(C_6NO_2H_4)_3. H_2O

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Chinese Journal of Structural Chemistry 1997年第5期16卷 376-379页

作者： ZI Feng-Lan zhou yin-zhuang TU Shu-Jie LIU Shun-Cheng(Department of Chemistry, Capital Nimal University, Beijing, 100037)JIN Xiang-Lin(Institute of Physical Chemistry, Beijing University, Beijing, 100871) Department of Chemistry Capital Normal University Beijing 100037 China Institute of Physical Chemistry Beijing University Beijing 100871 China

The reaction of CoCl2. 6H2O with picolinic acid gives the title compound Co-(C6NO3H4)3. H2O at room temperature. The crystallographic data for Co(C6NO3H5)3. H2O: monoclinic, space group C2/c, a= 29. 8316(6), b= 8. 573(2),c= 13. 835(3) , β= 95. 93(3)°, Z= 16, Mr=443. 3, Dc= 1. 673 g/cm3, μ(MoKa)= 1. 109 mm-1, F (000) = 1808, R =0. 036, R. =0.048 for 2497 independent observed reflections [F≥4.0σ(F)]. The Co atom is coordinated by three oxygen andthree nitrogen atoms, forming a distorted octahedral coordination geometry. In the unitcell, two kinds of isomerides are included. They are the mirror images to each other.

关键词： synthesis crystal structure cobalt complex isomer

Performances of fissured red sandstone after thermal treatment with constant-amplitude and low-cycle impacts

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 561-587页

作者： Yongjun Chen Tubing yin P.G.Ranjith Xibing Li Qiang Li Dengdeng zhuang School of Resources and Safety Engineering Central South UniversityChangsha410083China Department of Civil Engineering Monash UniversityMelbourne3800Australia Oulu Mining School University of OuluOuluFI-90014Finland

In the engineering practices,it is increasingly common to encounter fractured rocks perturbed by temperatures and frequent dynamic *** this paper,the dynamic behaviors and fracture characteristics of red sandstone considering temperatures(25℃,200℃,400℃,600℃,and 800℃)and fissure angles(0°,30°,60°,and 90°)were evaluated under constant-amplitude and low-cycle(CALC)impacts actuated by a modified split Hopkinson pressure bar(SHPB)***,fracture morphology and second-order statistics within the grey-level co-occurrence matrix(GLCM)were examined using scanning electron microscopy(SEM).Meanwhile,the deep analysis and discussion of the mechanical response were conducted through the synchronous thermal analyzer(STA)test,numerical simulations,one-dimensional stress wave theory,and material *** multiple regression models between response variables and interactive effects of independent variables were established using the response surface method(RSM).The results demonstrate the fatigue strength and life diminish as temperatures rise and increase with increasing fissure angles,while the strain rate exhibits an inverse ***,the peak stress intensification and strain rate softening observed during CALC impact exhibit greater prominence at increased fissure *** failure is dominated by tensile damage with concise evolution paths and intergranular cracks as well as the compressor-crushed zone which may affect the failure mode after 400℃.The second-order statistics of GLCM in SEM images exhibit a considerable dependence on the ***,thermal damage dominated by thermal properties controls the material structure and wave impedance and eventually affects the incident wave *** tensile wave reflected from the fissure surface is the inherent mechanism responsible for the angle effect exhibited by the fatigue strength and ***,the peak stress intensification and strain rate softening during impact are determ

关键词： Red sandstone Temperature Fissure Constant-amplitude and low-cycle(CALC) impact Fatigue failure Response surface method(RSM)

Microbiome-friendly PS/PVP electrospun fibrous membrane with antibiofilm properties for dental engineering

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Regenerative Biomaterials 2024年第4期3卷 27-37页

作者： Jiamin Chen Jia Guo Xueyun Lu Derong yin Cuisong zhou Yuqing Li Xuedong zhou State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesDepartment of Operative Dentistry and EndodonticsWest China Hospital of StomatologySichuan UniversityChengduSichuan610041China Stomatological Hospital affiliated Suzhou Vocational Health College Department of Operative Dentistry and EndodonticsSuzhou215000China College of Chemistry Sichuan UniversityChengduSichuan610064China

Dental caries is one of the most prevalent and biofilm-associated oral diseases in *** mutans,with a high ability to form biofilms by adhering to hard surfaces,has been established as an important etiological agent for dental ***,it is crucial to find a way to prevent the formation of cariogenic ***,we report an electrospun fibrous membrane that could inhibit the adhesion and biofilm formation of ***,the polystyrene(PS)/polyvinyl pyrrolidone(PVP)electrospun fibrous membrane altered the 3D biofilm architecture and decreased water-insoluble extracellular polysaccharide ***,the anti-adhesion mechanism which laid in Coulomb repulsion between the negatively charged PS/PVP electrospun fibrous membrane and *** was detected by zeta ***,metagenomics sequencing analysis and CCK-8 assay indicated that PS/PVP electrospun fibrous membrane was microbiome-friendly and displayed no influence on the cell viability of human gingival epithelial cells and human oral ***,an in vitro simulation experiment demonstrated that PS/PVP electrospun fibrous membrane could decrease colony-forming unit counts of *** effectively,and PS/PVP electrospun fibrous membrane carrying calcium fluoride displayed better anti-adhesion ability than that of PS/PVP electrospun fibrous membrane ***,this research showed that the PS/PVP electrospun fibrous membrane has potential applications in controlling and preventing dental caries.

关键词： Streptococcus mutans PS/PVP electrospun fibrous membrane biofilm(s) anti-adhesion Coulomb repulsion

Transient stimulated Raman scattering spectroscopy and imaging

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Light(Science & Applications) 2024年第4期13卷 654-663页

作者： Qiaozhi Yu Zhengjian Yao Jiaqi zhou Wenhao Yu Chenjie zhuang Yafeng Qi Hanqing Xiong National Biomedical Imaging Center College of Future TechnologyPeking UniversityBeijing 100871China Biomedical Engineering Department College of Future TechnologyPeking UniversityBeijing 100871China

Stimulated Raman scattering(SRS)has been developed as an essential quantitative contrast for chemical imaging in recent ***,while spectral lines near the natural linewidth limit can be routinely achieved by state-of-the-art spontaneous Raman microscopes,spectral broadening is inevitable for current mainstream SRS imaging *** is because those SRS signals are all measured in the frequency *** is a compromise between sensitivity and spectral resolution:as the nonlinear process benefits from pulsed excitations,the fundamental time-energy uncertainty limits the spectral ***,the spectral range and acquisition speed are mutually *** we report transient stimulated Raman scattering(T-SRS),an alternative time-domain strategy that bypasses all these fundamental conjugations.T-SRS is achieved by quantum coherence manipulation:we encode the vibrational oscillations in the stimulated Raman loss(SRL)signal by femtosecond pulse-pair sequence excited vibrational wave packet *** Raman spectrum was then achieved by Fourier transform of the time-domain SRL *** all Raman modes are impulsively and simultaneously excited,T-SRS features the natural-linewidth-limit spectral line shapes,laser-bandwidth-determined spectral range,and improved ***~150-fs laser pulses,we boost the sensitivity of typical Raman modes to the sub-mM *** all-plane-mirror high-speed time-delay scanning,we further demonstrated hyperspectral SRS imaging of live-cell metabolism and high-density multiplexed imaging with the natural-linewidth-limit spectral resolution.T-SRS shall find valuable applications for advanced Raman imaging.

关键词： scattering excited mutually