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Evaluation of a user-friendly CSDS cage apparatus for studying depressive-like behaviors in rodents
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作者 Hao Zhang Dongmei Gao +6 位作者 Minghu Hu Wanqing Zhou Muxuan Han Ya Sun Yang Zhang Jieqiong Wang Mingzhou Gao 《Animal Models and Experimental Medicine》 2025年第1期179-186,共8页
Background:Previously,a chronic social defeat stress(CSDS)model has been widely-adopted for assessing depressive-like behaviors in animals.However,there is still room for improvement in the CSDS model to safeguard stu... Background:Previously,a chronic social defeat stress(CSDS)model has been widely-adopted for assessing depressive-like behaviors in animals.However,there is still room for improvement in the CSDS model to safeguard study accuracy and the wel-fare of lab rodents.Our study team developed a novel,standardized apparatus to induce CSDS in rodents and assessed the model's practical adaptability.Methods:An innovative CSDS cage apparatus and water bottle was designed.To evaluate the effectiveness of the newly developed tools,a variety of animal models,including the tail suspension test(TST),sucrose preference test,forced swimming test(FST),novelty-suppressed feeding test,female urine sniffing test,and open field test(OFT),were adopted to assess depressive-like behaviors in mice.Fluoxetine treat-ment was also administered to observe the reversal effect,as part of the validation.Results:The CSDS cage apparatus resulted in the manifestation of depressive-like behaviors in the model mice.Significant reductions in sucrose preference and urine sniffing time were observed,while the OFT revealed decreased central zone total distance,residence time,and frequency of entry.Moreover,increased immobility was found in the FST and TST.Fluoxetine treatment was found to successfully reverse the modeling effect.Conclusion:The CSDS cage apparatus was validated for enhanced usability and ad-dressed the previous challenges of water bottle leakage and lab rodent welfare is-sues.The consistent results from multiple behavioral tests also supported real-world application of the apparatus,offering researchers a promising alternative to conven-tional rodent cages. 展开更多
关键词 CSDS DEPRESSION experimental cage leak-proof water bottle methodology
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Enhancing the activity,selectivity,and recyclability of Rh/PPh_(3) system‐catalyzed hydroformylation reactions through the development of a PPh_(3)‐derived quasi‐porous organic cage as a ligand 被引量:4
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作者 Wenlong Wang Cunyao Li +7 位作者 Heng Zhang Jiangwei Zhang Lanlu Lu Zheng Jiang Lifeng Cui Hongguang Liu Li Yan Yunjie Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第7期1216-1226,共11页
In contrast to heterogeneous network frameworks(e.g.,covalent organic frameworks and metal‐organic frameworks)and porous organic polymers,porous organic cages(POCs)are soluble molecules in common organic solvents tha... In contrast to heterogeneous network frameworks(e.g.,covalent organic frameworks and metal‐organic frameworks)and porous organic polymers,porous organic cages(POCs)are soluble molecules in common organic solvents that provide significant potential for homogeneous catalysis.Herein,we report a triphenylphosphine‐derived quasi‐porous organic cage(denoted as POC‐DICP)as an efficient organic molecular cage ligand for Rh/PPh_(3) system‐catalyzed homogeneous hydroformylation reactions.POC‐DICP not only displays enhanced hydroformylation selectivity(aldehyde selectivity as high as 97%and a linear‐to‐branch ratio as high as 1.89)but can also be recovered and reused via a simple precipitation method in homogeneous reaction systems.We speculate that the reason for the high activity and good selectivity is the favorable geometry(cone angle=123.88°)and electronic effect(P site is relatively electron‐deficient)of POC‐DICP,which were also demonstrated by density functional theory calculations and X‐ray absorption fine‐structure characterization. 展开更多
关键词 HYDRofORMYLATION TRIPHENYLPHOSPHINE Porous organic cages Chemical selectivity Linear‐regioselectivity
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Selective photosynthesis of Z-olefins through crystalline metal-organic cage-initiated expeditious cascade reactions
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作者 Jia-Ni Lu Yunze Huang +6 位作者 Yuan-Sheng Xia Long-Zhang Dong Lei Zhang Jing-Jing Liu Lan-Gui Xie Jiang Liu Ya-Qian Lan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期118-131,共14页
The semi-hydrogenation of alkyne to form Z-olefins with high conversion and high selectivity is still a huge challenge in the chemical industry.Moreover,flammable and explosive hydrogen as the common hydrogen source o... The semi-hydrogenation of alkyne to form Z-olefins with high conversion and high selectivity is still a huge challenge in the chemical industry.Moreover,flammable and explosive hydrogen as the common hydrogen source of this reaction increases the cost and danger of industrial production.Herein,we connect the photocatalytic hydrogen evolution reaction and the semihydrogenation reaction of alkynes in series and successfully realize the high selective production of Z-alkenes using low-cost,safe,and green water as the proton source.Before the cascade reaction,a series of isomorphic metal–organic cage catalysts(Co_(x)Zn_(8−x)L_(6),x=0,3,4,5,and 8)are designed and synthesized to improve the yield of the photocatalytic hydrogen production.Among them,Co_(5)Zn_(3)L_(6) shows the highest photocatalytic activity,with a H_(2) generation rate of 8.81 mmol g^(−1) h^(−1).Then,Co_(5)Zn_(3)L_(6) is further applied in the above tandem reaction to efficiently reduce alkynes to Z-alkenes under ambient conditions,which can reach high conversion of>98%and high selectivity of>99%,and maintain original catalytic activity after multiple cycles.This“one-pot”tandem reaction can achieve a highly selective and safe stepwise conversion from water into hydrogen into Z-olefins under mild reaction conditions. 展开更多
关键词 alkyne semi-hydrogenation hydrogen evolution reaction metal-organic cages photocatalysis Z-olefins
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Dynamic Analysis of Hydrodynamic Behavior of A Flatfish Cage System Under Wave Conditions 被引量:3
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作者 崔勇 关长涛 +2 位作者 万荣 黄滨 李娇 《China Ocean Engineering》 SCIE EI CSCD 2014年第2期215-226,共12页
This paper presents a simulation model based on the finite element method. The method is used to analyze the motion response and mooring line tension of the flatfish cage system in waves. The cage system consists of t... This paper presents a simulation model based on the finite element method. The method is used to analyze the motion response and mooring line tension of the flatfish cage system in waves. The cage system consists of top frames, netting, mooring lines, bottom frames, and floats. A series of scaled physical model tests in regular waves are conducted to verify the numerical model. The comparison results show that the simulated and the experimental results agree well under the wave conditions, and the maximum pitch of the bottom frame with two orientations is about 12o. The motion process of the whole cage system in the wave can be described with the computer visualized technology. Then, the mooring line tensions and the motion of the bottom frame with three kinds of weight are calculated under different wave conditions. According to the numerical results, the differences in mooring line tensions of flatfish cages with three weight modes are indistinct. The maximum pitch of the bottom frame decreases with the increase of the bottom weight. 展开更多
关键词 flatfish cage hydrodynamic behavior dynamic analysis WAVES
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Effects of anions on the structural regulation of Zn‑salen‑modified metal‑organic cage
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作者 GUO Qiaojia CAI Junkai DUAN Chunying 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2203-2211,共9页
By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variationa... By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold. 展开更多
关键词 metal-organic cage Zn-salen host-guest electrostatic interaction ANIONS structural regulation
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Research of caged dynamics of clusters center atoms in Pd_(82)Si_(18) amorphous alloy
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作者 邓永和 陈贝 +5 位作者 祁清华 李兵兵 高明 文大东 王小云 彭平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期623-629,共7页
To date,there is still a lack of a comprehensive explanation for caged dynamics which is regarded as one of the intricate dynamic behaviors in amorphous alloys.This study focuses on Pd_(82)Si_(18)as the research objec... To date,there is still a lack of a comprehensive explanation for caged dynamics which is regarded as one of the intricate dynamic behaviors in amorphous alloys.This study focuses on Pd_(82)Si_(18)as the research object to further elucidate the underlying mechanism of caged dynamics from multiple perspectives,including the cage's lifetime,atomic local environment,and atomic potential energy.The results reveal that Si atoms exhibit a pronounced cage effect due to the hindrance of Pd atoms,resulting in an anomalous peak in the non-Gaussian parameters.An in-depth investigation was conducted on the caged dynamics differences between fast and slow Si atoms.In comparison to fast Si atoms,slow Si atoms were surrounded by more Pd atoms and occupied lower potential energy states,resulting in smaller diffusion displacements for the slow Si atoms.Concurrently,slow Si atoms tend to be in the centers of smaller clusters with coordination numbers of 9 and 10.During the isothermal relaxation process,clusters with coordination numbers 9 and 10 have longer lifetimes,suggesting that the escape of slow Si atoms from their cages is more challenging.The findings mentioned above hold significant implications for understanding the caged dynamics. 展开更多
关键词 caged dynamics Pd_(82)Si_(18) amorphous alloy fast and slow atoms CLUSTERS lifetime
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Hydrodynamic coefficients of a simplified floating system of gravity cage in waves 被引量:1
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作者 Chang-wen WU Fu-kun GUI +1 位作者 Yu-cheng LI Wei-huan FANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第5期654-663,共10页
Numerical simulation and experimental tests were carried out to examine the hydrodynamic behaviors of a double-column floating system of gravity cage under wave conditions. A floating system of gravity cage can be tre... Numerical simulation and experimental tests were carried out to examine the hydrodynamic behaviors of a double-column floating system of gravity cage under wave conditions. A floating system of gravity cage can be treated as a small-sized floating structure when compared with the wavelengths. The main problem in calculating the wave loads on the small-sized floating structure is to obtain the reasonable force coefficients, which may differ from a submerged structure. In this paper, the floating system of gravity cage is simplified to a 2D problem, where the floating system is set symmetrically under wave conditions. The motion equations were deduced under wave conditions and a specific method was proposed to resolve the problem of wave forces acting on a small-sized floating system of gravity cage at water surface. Results of the numerical method were compared with those from model tests and the hydrodynamic coefficients Cn and Cr were studied. It is found that Cn ranges from 0.6 to 1.0 while Cr is between 0.4 and 0.6 in this study. The results are useful for research on the hydrodynamic behavior of the deep-water gravity sea cages. 展开更多
关键词 Gravity cage Floating system Hydrodynamic coefficients WAVES
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Dynamic Behavior and Deformation Analysis of the Fish Cage System Using Mass-Spring Model 被引量:4
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作者 Chun Woo LEE Jihoon LEE Subong PARK 《China Ocean Engineering》 SCIE EI CSCD 2015年第3期311-324,共14页
Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being c... Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being cultivated. Structural durability of the system against environmental factors has been major concern for the marine aquaculture system. In this research, a mathematical model and a simulation method were presented for analyzing the performance of the large-scale fish cage system influenced by current and waves. The cage system consisted of netting, mooring ropes, floats, sinkers and floating collar. All the elements were modeled by use of the mass-spring model. The structures were divided into finite elements and mass points were placed at the mid-point of each element, and mass points were connected by springs without mass. Each mass point was applied to external and internal forces, and total force was calculated in every integration step. The computation method was applied to the dynamic simulation of the actual fish cage systems rigged with synthetic fiber and copper wire simultaneously influenced by current and waves. Here, we also tried to find a relevant ratio between buoyancy and sinking force of the fish cages. The simulation results provide improved understanding of the behavior of the structure and valuable information concerning optimum ratio of the buoyancy to sinking force according to current speeds. 展开更多
关键词 fish cage mathematical model aquaculture computer simulation mass-spring model
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Dynamic Analysis for the Global Performance of An SPM-Feeder-Cage System Under Waves and Currents 被引量:2
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作者 Cristian CIFUENTES M.H.KIM 《China Ocean Engineering》 SCIE EI CSCD 2015年第3期415-430,共16页
In the present study, the dynamic response of a coupled SPM-feeder-cage system under irregular waves and shear currents is analyzed. A numerical model is developed by using the commercial software Orca Flex. Hydrodyna... In the present study, the dynamic response of a coupled SPM-feeder-cage system under irregular waves and shear currents is analyzed. A numerical model is developed by using the commercial software Orca Flex. Hydrodynamics coefficients of the vessel are calculated by using a 3D diffraction/radiation panel program. First- and second-order wave forces are included in the calculations. Morison equation is used to compute the drag force on line elements representing the net. Drag coefficients are determined at every time step in the simulation considering the relative normal velocity between the structural elements and the fluid flow. The dynamic response of the coupled system is analyzed for various environments and net materials. The results of the study show the effects of solidity ratio of the net and vertical positions of the cage on the overall dynamic response of the system, confirming the viability of this type of configuration for future development of offshore aquaculture in deep waters. 展开更多
关键词 offshore aquaculture SPM(single point mooring) feeder vessel connecting lines operational/survival environment drag force equivalent net cage grouping net modeling line tensions solidity ratio
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Porous Organic Cage‑Based Quasi‑Solid‑State Electrolyte with Cavity‑Induced Anion‑Trapping Effect for Long‑Life Lithium Metal Batteries
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作者 Wei-Min Qin Zhongliang Li +7 位作者 Wen‑Xia Su Jia‑Min Hu Hanqin Zou Zhixuan Wu Zhiqin Ruan Yue‑Peng Cai Kang Li Qifeng Zheng 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期376-386,共11页
Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testifie... Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical battery.Herein,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 eV.These allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 h.As a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 cycles.Therefore,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries. 展开更多
关键词 Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery
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Effects of rearing system(floor vs.cage)and sex on performance,meat quality and enteric microorganism of yellow feather broilers
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作者 WANG Lai-di ZHANG Yang +6 位作者 KONG Ling-ling WANG Zhi-xiu BAI Hao JIANG Yong Bl Yu-lin CHANG Guo-bin CHEN Guo-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第7期1907-1920,共14页
This study investigated the effects of floor and cage rearing systems on performance,meat quality,and enteric microorganisms of male and female yellow feather broilers.Two hundred Xueshan chickens(42 days old;100 of e... This study investigated the effects of floor and cage rearing systems on performance,meat quality,and enteric microorganisms of male and female yellow feather broilers.Two hundred Xueshan chickens(42 days old;100 of each sex)were divided into four groups,according to sex and rearing system(stainless-steel cage or litter floor).Male and cage-reared broilers exhibited better(P<0.001)performance and higher(P≤0.001)eviscerated percentage than female and floor-reared broilers.The interaction between rearing system and sex had an effect(P<0.05)on the percentage of breast and thigh muscles.Female floor-reared broilers presented the highest(P<0.02)percentage of breast and thigh muscles among all the groups.In both sexes,the abdominal fat content in cage-reared broilers was higher(P<0.01)than that in floor-reared broilers.Female cage-reared broilers exhibited better(P<0.05)meat quality of breast muscle than other groups.An analysis of welfare observations indicated that the feather quality of floor-reared broilers was better(P<0.01)than that of cage-reared broilers,whereas the gait scores were not significantly affected(P>0.05)by rearing system.The enteric microbiota assessment by 16 S rRNA amplicon-based sequencing showed that Firmicutes,Proteobacteria,and Bacteroidetes were the most prevalent phyla in both rearing systems,and that the cecum was relatively stable in terms of microbiome composition.Floor-reared broilers exhibited a richer diversity of bacteria in the intestinal tract than cage-reared broilers,while alpha diversity was not significantly different(P>0.05)among the groups.The ratio of Bacteroidetes to Firmicutes and the abundance of Helicobacter and Romboutsia could potentially affect the production of broilers.These findings indicate that cage rearing improved the production of male Xueshan broilers,which may be due to the difference in enteric microbiota between cage and floor rearing systems. 展开更多
关键词 cage rearing yellow feather broilers PERFORMANCE meat quality microbiome
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Study on Loading Leaves Density with Cage Clamp on Quality of Cured Tobaccos in Bulk-Curing Barn
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作者 王能如 余金恒 +2 位作者 罗荣欣 林北森 尹永强 《Agricultural Science & Technology》 CAS 2014年第8期1317-1321,共5页
In order to determine the best loading density of tobacco leaf with cage clamp in bulk-curing barns, a curing test was conducted on middle-part tobacco leaves. The results showed that for good appearance quality of cu... In order to determine the best loading density of tobacco leaf with cage clamp in bulk-curing barns, a curing test was conducted on middle-part tobacco leaves. The results showed that for good appearance quality of cured tobacco, the loading density at 59.52 kg/m2 (4 000 kg/barn) was the best, fol owed by 66.96 kg/m2 (4 500 kg/barn) and 74.40 kg/m2 (5 000 kg/barn). As leaf loading density increased, the contents of leaf nicotine and total nitrogen increased, sugar content had smal changes, the ratio of sugar to nicotine decreased and tended to be balanced and the content of neutral aroma substances was decreasing, but the difference among treatments was not significant. With the increase of loading density, the sensory quality of cured leaf was better. When leaf loading density was 66.96 kg/m2 (4 500 kg/barn), apperance quality of cured leaf improved considerably, with prominent aro-ma. Therefore, the best loading density of tobacco leaf in cage clamp of bulk-curing barn would be 66.96 kg/m2 (4 500 kg/barn) . 展开更多
关键词 Flue-cured tobacco Bulk curing Tobacco quality cage clamp Loadingleaves density
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Synthesis and Structure of A Novel Caged Bicyclic Phosphate Flame Retardant 被引量:28
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作者 Li, X Ou, YX +1 位作者 Zhang, YH Lian, DJ 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第10期887-890,共4页
PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octa... PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane (PEPA) and phosphorus oxychloride in this paper. Its structure was characterized by elemental analysis. FTIR, H-1 NMR. P-31 NMR and X-ray diffraction analysis. 展开更多
关键词 caged bicyclic phosphate flame retardant crystal structure
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Numerical simulation of the influences of sinker weight on the deformation and load of net of gravity sea cage in uniform flow 被引量:17
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作者 LI Yucheng ZHAO Yunpeng +2 位作者 GUI Fukun TENG Bin DONG Guohai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第3期125-137,共13页
A numerical model for determining fishing net configuration and load is developed, based on the lumped masses method. The model is used to analyze the influences on the net of gravity sea cage by different sinker weig... A numerical model for determining fishing net configuration and load is developed, based on the lumped masses method. The model is used to analyze the influences on the net of gravity sea cage by different sinker weights in uniform flow. The net of gravity sea cage is simulated under different current velocities and sinker weights. In order to verify the validity of the numerical results, model test results made by Lader and Enerhaug are cited and compared with the numerical ones. The results of numerical simulation agree well with the experimental ones and the agreement is within an error range of 13% under different velocities and sinker weights. The numerical results indicate that increasing the sinker weight can effectively reduce the net deformation, but the total drag force on the net will increase accordingly. Results will give references for better knowledge of the hydrodynamic behavior of gravity sea cage. 展开更多
关键词 sea cage numerical simulation lumped mass method sinker weight
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Photochemical Reaction of Benzoin Caged Compound: Time-Resolved Fourier Transform Infrared Spectroscopy Study
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作者 代小娟 余友清 +1 位作者 刘坤辉 苏红梅 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期91-98,I0002,共9页
The benzoin group caged compound has received strong interests due to its excellent photo- deprotection properties and wide use in chemical and biological studies. We used timeresolved infrared spectroscopy to investi... The benzoin group caged compound has received strong interests due to its excellent photo- deprotection properties and wide use in chemical and biological studies. We used timeresolved infrared spectroscopy to investigate the photochemical reaction of the benzoin caged compound, o-(2-methylbenzoyl)-DL-benzoin under 266 nm laser irradiation. Taking advantage of the specific vibrational marker bands and the IR discerning capability, we have detected and identified the uncaging product 2-methylbenzoic acid, and two intermediate radicals of benzoyl and 2-methylbenzoate benzyl in the transient infrared spectra. Our results provide spectral evidence to support the homolytic cleavage reaction of C-C=O bond in competition with the deprotection reaction. Moreover, the product yields of 2-methylbenzoic acid and benzoyl radical were observed to be affected by solvents and a largely water contalning solvent can be in favor of the deprotection reaction. 展开更多
关键词 BENZOIN caged compound Photo-deprotection Time-resolved infrared spectroscopy
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Forms and Balance of Nitrogen and Phosphorus in Cage Culture Waters in Guangdong Province, China 被引量:9
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作者 WEN Yanmao WEI Xiange +4 位作者 SHU Tingfei ZHOU Jingfeng YU Guanghui LI Feng HUANG Yanyun 《Chinese Geographical Science》 SCIE CSCD 2007年第4期370-375,共6页
In order to approach the characteristics of nitrogen and phosphorus pollution caused by cage culture and the balance of nitrogen and phosphorus during the process of cage culture, a monitoring was conducted in Daya Ba... In order to approach the characteristics of nitrogen and phosphorus pollution caused by cage culture and the balance of nitrogen and phosphorus during the process of cage culture, a monitoring was conducted in Daya Bay of Guangdong Province, China from April 2002 to Jane 2003. The results show that the concentrations of total nitrogen (TN) in the waters at the sites with five and ten years of cage culture history are 1.8 and 2.3 times of that at control site respectively. Ammonium (NH3-N) is the main form of nitrogen in spring while nitrate (NO~) in winter. The concentrations of TN, total dissolved nitrogen (TDN) and dissolved organic nitrogen (DON) are highest in autumn. The concentration of phosphorus increases with the increasing of the culturing time, among which phosphate ( PO^-34) increases most obviously. The concentrations of total phosphorus (TP) and total dissolved phosphorus (TDP) are highest in autumn. The nitrogen and phosphorus are accumulated significantly in the sediment of cage culture area. The model of N balance in the cage culture area: bait (70.62%) + fry (0.28%) + input by tide (14.8%) + release from sediment 04.3%) = harvest of adult fish (12.07%) + deposition into sediment (28.75%) + output by tide (56.18%) + others (3.00%). The model of P balance: bait (83.11%) + fry (0.17%) + input by tide (12.23%) + release from sediment (4.49%) = harvest of adult fish (8.43%) + deposition into sediment (48.59%) + output by tide (41.94%) + others (1.04%). In one fish growth year, the contents of nitrogen and phosphorus in harvest of adult fish are only 17.0% and 10.1% of the contents of nitrogen and phosphorus in fish bait and fry, wherein 83% of nitrogen and more than 89% of phosphorus in fish bait became marine pollutants. 展开更多
关键词 cage culture environment impact NITROGEN PHOSPHORUS Daya Bay Guangdong Province
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Dynamic Stability Analysis of Cages in High-Speed Oil-Lubricated Angular Contact Ball Bearings 被引量:13
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作者 刘秀海 邓四二 滕弘飞 《Transactions of Tianjin University》 EI CAS 2011年第1期20-27,共8页
To investigate the cage stability of high-speed oil-lubricated angular contact ball bearings, a dynamic model of cages is developed on the basis of Gupta’s and Meeks’ work. The model can simulate the cage motion und... To investigate the cage stability of high-speed oil-lubricated angular contact ball bearings, a dynamic model of cages is developed on the basis of Gupta’s and Meeks’ work. The model can simulate the cage motion under oil lubrication with all six degrees of freedom. Particularly, the model introduces oil-film damping and hysteresis damping, and deals with the collision contact as imperfect elastic contact. In addition, the effects of inner ring rotational speed, the ratio of pocket clearance to guiding clearance and applied load on the cage stability are investigated by simulating the cage motion with the model. The results can provide a theoretical basis for the design of ball bearing parameters. 展开更多
关键词 dynamic analysis high-speed angular contact ball bearing cage STABILITY SIMULATION
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Numerical Simulation of Hydrodynamic Behaviors of Gravity Cage in Waves 被引量:10
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作者 赵云鹏 李玉成 +1 位作者 董国海 桂福坤 《China Ocean Engineering》 SCIE EI 2007年第2期225-238,共14页
This paper aims at investigation of the dynamic properties of gravity cage exposed to waves by use of a numerical model. The numerical model is developed, based on lumped mass method to set up the equations of motion ... This paper aims at investigation of the dynamic properties of gravity cage exposed to waves by use of a numerical model. The numerical model is developed, based on lumped mass method to set up the equations of motion of the whole cage; meanwhile the solutions of equations are solved by the Runge-Kutta-Vemer fifth-order and sixth-order method. Physical model tests have been carried out to examine the validity of the numerical model. The results by the numerical simulation agree well with the experimental data. 展开更多
关键词 gravity cage numerical simulation hunped mass method model tests
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Numerical Analysis on the Effects of Submerged Depth of the Grid and Direction of Incident Wave on Gravity Cage 被引量:12
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作者 陈昌平 李玉成 +2 位作者 赵云鹏 董国海 桂福坤 《China Ocean Engineering》 SCIE EI 2009年第2期233-250,共18页
In this paper, the numerical model of the net cage with the grid mooring system in waves is set up by the lumped mass method and rigid kinematics theory, and then the motion equations of floating system, net system, m... In this paper, the numerical model of the net cage with the grid mooring system in waves is set up by the lumped mass method and rigid kinematics theory, and then the motion equations of floating system, net system, mooring system, and floaters are solved by the Runge-Kutta fifth-order method. For the verification of the numerical model, a series of physical model tests have been carried out. According to the comparisons between the simulated and experimental results, it can be found that the simulated and experimental results agree well in each condition. Then, the effects of submerged depth of grid and direction of incident wave propagation on hydrodynamic behaviors of the net cage are analyzed. According to the simulated results, it can be found that with the increase of submerged depth of grid, the forces acting on mooring lines and bridle lines increase, while the forces on grid lines decrease; the horizontal motion amplitudes of floating collar decrease obviously, while the vertical motion amplitudes of floating collar change little. When the direction of incident wave propagation changes, forces on mooring lines and motion of net cage also change accordingly. When the propagation direction of incident wave changes from 0° to 45°, forces on the main ropes and bridle ropes increase, while the forces on the grid ropes decrease. With the increasing propagation direction of incident wave, the horizontal amplitude of the forces collar decreases, while the vertical amplitude of the floating collar has little variation. 展开更多
关键词 submerged depth of grid gravity cage physical model test numerical simulation
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Experimental characterization of guest molecular occupancy in clathrate hydrate cages: A review 被引量:5
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作者 Changhong Yu Litao Chen Baojiang Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第9期2189-2206,共18页
Study on the microscopic structure of clathrate hydrate has made significant progress in the past decades.This review aims to summarize the state of the art of the experimental characterization of guest molecular occu... Study on the microscopic structure of clathrate hydrate has made significant progress in the past decades.This review aims to summarize the state of the art of the experimental characterization of guest molecular occupancy in clathrate hydrate cages,which is an important area of the microscopic structures.The characterizing method and features of different guest molecular,such as hydrocarbon,carbon dioxide,hydrogen and inhibitor/promoter,in different hydrate cages have been extensively reviewed.A comprehensive use of advanced technologies such as X-ray diffraction,Raman spectroscopy and nuclear magnetic resonance may provide better understanding on the compositions and microscopic mechanisms of clathrate hydrate. 展开更多
关键词 CLATHRATE HYDRATE cage OCCUPANCY Experimental characterization PXRD Raman NMR
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