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The release and catabolism of ferulic acid in plant cell wall by rumen microbes:A review

Animal Nutrition 2022年第2期9卷 335-344页

作者： Yan-Lu Wang Wei-Kang Wang qi-chao wu Hong-Jian Yang State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Ferulic acid(FA)is one of the most abundant hydroxycinnamic acids in the plant world,especially in the cell wall of grain bran,in comparison with forage and crop *** studies noted that FA was mainly linked with arabinoxylans and lignin in plant cell walls in ester and ether covalent *** forages were ingested by ruminant animals or encountered rumen microbial fermentation in vitro,these cross-linkages form physical and chemical barriers to protect cell-wall carbohydrates from microbial attack and enzymatic ***,increasing studies noted that FA presented some toxic effect on microbial growth in the *** recent decades,many studies have addressed the relationships of ester and/or ether-linked FA with rumen nutrient digestibility,and there is still some controversy whether these linkages could be used as a predicator of forage digestibility in *** authors in this review summarized the possible relationships between ester and/or ether-linked FA and fiber digestion in *** microbes,especially bacteria and fungi,were found capable of breaking down the ester linkages within plant cell walls by secreting feruloyl and p-coumaroyl esterase,resulting in the release of free FA and improvement of cell wall *** increasing evidence noted that these esterases secreted by rumen microbes presented synergistic effects with xylanase and cellulase to effectively hydrolyze forage cell *** released FA were absorbed through the rumen wall directly and entered into blood circulation and presented antioxidant effects on host *** others were partially catabolized into volatile fatty acids by rumen microbes,and the possible catabolic pathways *** better understand plant cell wall degradation in the rumen,the metabolic fate of FA along with lignin decomposition mechanisms are needed to be explored via future microbial isolation and incubation studies with aims to maximize dietary fiber intake

关键词： Rumen microbes Ferulic acid Fiber digestion

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In-situ Enhanced Toughening of Poly（ethylene terephthalate）/elastomer Blends via Gamma-Ray Radiation at Presence of Trimethylolpropane Triacrylate

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Chinese Journal of Chemical Physics 2016年第6期29卷 703-709,I0001,I0002页

作者： Li-zhao Xie Le-chen Chen Mo-zhen Wang qi-chao wu Xiao Zhou Xue-wu Ge CASKeyLaboratoryofSoftMatterChemistry DepartmentofPolymerScienceandEngineeringUniversityofScienceandTechnologyofChinaHefei230026China GuangdongTiananNewMaterialCo. Ltd.Foshan528000China

Gamma-ray radiation has always been a convenient and effective way to modify the inter- facial properties in polymer blends. In this work, a small amount of trimethylolpropane triacrylate （TMPTA） was incorporated into poly（ethylene terephthalate）（PET）/random terpolymer elastomer （ST2000） blends by melt-blending. The existence of TMPTA would induce the crosslinking of PET and ST2000 molecular chains at high temperatures of blend- ing, resulting in the improvement in the impact strength but the loss in the tensile strength. When the PET/ST2000 blends were irradiated by gamma-ray radiation, the integrated me- chanical properties could be enhanced significantly at a high absorbed dose. The irradiated sample at a dose of 100 kGy even couldn＇t be broken under the impact test load, and at the same time, has nearly no loss of tensile strength. Based on the analysis of the impact- fractured surface morphologies of the blends, it can be concluded that gamma-ray radiation at high absorbed dose can further in situ enhance the interfacial adhesion by promoting the crosslinking reactions of TMPTA and polymer chains. As a result, the toughness and strength of PET/ST2000 blend could be dramatically improved. This work provides a facial and practical way to the fabrication of polymer blends with high toughness and strength.

关键词： Toughened PET blend Interracial interaction Gamma-ray radiation Radia- tion crosslink Trimethylolpropane triacrylate

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Synthesis and morphology control of raspberry-like poly(ethylene terephthalate)/polyacrylonitrile microspheres

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Chinese Chemical Letters 2016年第2期27卷 195-199页

作者： Yong-Fei Xu Mo-Zhen Wang qi-chao wu Xiao Zhou Xue-wu Ge CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China School of Materials and Chemical Engineering Anhui Jianzhu University Guangdong Tianan New Material Co. Ltd.

The fabrication of raspberry-like poly（ethylene terephthalate）/polyacrylonitrile（PET/PAN） microspheres by g-ray radiation-induced polymerization of acrylonitrile on micron-sized PET microspheres were first reported in this work. A PET emulsion was firstly prepared by dispersing a PET solution with 1,1,2,2-tetrachloroethane/phenol mixture as the solvent into an aqueous solution of sodium dodecyl ***, PET microspheres were formed by precipitating the PET emulsion droplets from ethanol. The influence of the PET solvent and the weight ratio of ethanol to PET emulsion on the morphology of the PET microspheres had been investigated. After the surface of the prepared PET microspheres was grafted with poly（acrylic acid）, the grafting polymerization of AN also had been successfully initiated by g-ray radiation to form PAN microspheres with a size of about 100 nm on the PET microspheres. This work provides a new method to fabricate micron-sized PET microspheres, and further expands the functionalization of PET and its application fields.

关键词： PET emulsion Emulsion precipitation PET microsphere Raspberry-like microsphere PET/PAN composite microspheres

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Melatonin for the treatment of spinal cord injury

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Neural Regeneration Research 2018年第10期13卷 1685-1692页

作者： Yan Zhang Wen-Xiu Zhang Yan-Jun Zhang Ya-Dong Liu Zong-Jian Liu qi-chao wu Yun Guan Xue-Ming Chen Central Laboratory Beijing Luhe HospitalCapital Medical University Department of Orthopedics Beijing Luhe HospitalCapital Medical University Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Department of Neurological Surgery Johns Hopkins University

Spinal cord injury（SCI） from trauma or disease severely impairs sensory and motor function. Neurorehabilitation after SCI is a complex medical process that focuses on improving neurologic function and repairing damaged connections in the central nervous system. An increasing number of preclinical studies suggest that melatonin may be useful for the treatment of SCI. Melatonin is an indolamine that is primarily secreted by the pineal gland and known to be regulated by photoperiodicity. However, it is also a versatile hormone with antioxidative, antiapoptotic, neuroprotective, and anti-inflammatory properties. Here, we review the neuroprotective properties of melatonin and the potential mechanisms by which it might be beneficial in the treatment of SCI. We also describe therapies that combine melatonin with exercise, oxytetracycline, and dexamethasone to attenuate the secondary injury after SCI and limit potential side effects. Finally, we discuss how injury at different spinal levels may differentially affect the secretion of melatonin.

关键词： spinal cord injury melatonin secondary damage neuroprotection antioxidative antiapoptotic anti-inflammatory synergistic effects neural regeneration

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Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research International 2024年第1期31卷 252-263页

作者： Guo-ning He Shi-qi Wan Bo Jiang chao-lei Zhang Ya-zheng Liu Chun-jing wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

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Regioselective C-C bond cleavage/aminocarbonylation cascade under copper catalysis

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Science China Chemistry 2024年第11期67卷 3798-3806页

作者： qi-chao Shan Yan Zhao Yong wu Hong-Fei Liu Xin-Hua Duan Li-Na Guo Department of Chemistry School of Chemistry Energy Research Center of Energy Storage Materials and Devices Ministry of EducationXi'an Jiaotong University State Key Laboratory of Applied Organic Chemistry Lanzhou University

A regioselective C-C bond cleavage/aminocarbonylation cascade is presented. In recent years, tremendous progress has been made in the alkoxyl radical-mediated C-C bond cleavage of unstrained monocarbocycles. In contrast, the deconstruction and functionalization of bicyclic skeletons has been less developed and has mainly focused on the ring expansion process. Inspired by the aromatization-driven C-C bond cleavage, here we demonstrate a ring-opening/aminocarbonylation cascade under copper catalysis, in which the formation of a stable γ-lactam or succinimide skeleton reverses the selectivity of C-C cleavage. Remarkably, the photo and thermal assistance is not required when the succinimide skeleton is formed during the ring opening process. DFT calculations revealed that this unexpected ring-opening process is thermodynamically and kinetically favourable.

关键词： C-C bond cleavage controllable regioselectivity aminocarbonylation bicyclic alkoxy radical

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Wheat silage partially replacing oaten hay exhibited greater feed efficiency and fibre digestion despite low feed intake by feedlot lambs

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Animal Nutrition 2023年第4期15卷 332-340页

作者： Zhao-Yang Cui Wen-Juan Li Wei-Kang Wang qi-chao wu Yao-Wen Jiang Ailiyasi Aisikaer Fan Zhang He-Wei Chen Hong-Jian Yang State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

This study aimed to investigate the feeding effect of wheat silage on growth performance,nutrient digestibility,rumen fermentation,and microbiota composition in feedlot ***-four male crossbred Chinese Han lambs(BW=27.8±0.67 kg,3 months of age)were randomly assigned to four ration groups with wheat silage replacing 0%(WS0),36%(WS36),64%(WS64),and 100%(WS100)of oaten hay on forage dry matter *** concentrate-to-forage ratio was 80:20 and the feeding trial lasted 52 *** wheat silage inclusion linearly decreased dry matter intake by 4%to 27%(P<0.01).However,increasing the wheat silage replacement of oaten hay by no more than 64%improved the feed efficiency by 14%as noted by the feed-to-gain ratio(P=0.04).Apparent digestibility of organic matter(P<0.01),neutral detergent fibre(P=0.04)and acid detergent fibre(P<0.01)quadratically *** nitrogen(P=0.01)decreased while microbial protein production(P<0.01)increased with the increase of wheat silage *** volatile fatty acids concentration increased quadratically with the increase of wheat silage inclusion(P<0.01),and the highest occurred in *** molar proportion of acetate(P<0.01)and acetate-to-propionate ratio(P=0.04)decreased while butyrate(P<0.01)and isovalerate(P=0.04)*** wheat silage inclusion increased the Firmicutes-toBacteroidota ratio by 226%to 357%,resulting in Firmicutes instead of Bacteroidota being the most abundant *** relative abundance of cellulolytic Ruminococcus numerically increased but that of amylolytic Prevotella(P<0.01)decreased as increasing wheat silage *** together,increasing wheat silage replacement of oaten hay by no more than 64%exhibited greater feed efficiency and fibre digestion despite low feed intake by feedlot lambs due to the change of Firmicutes-to-Bacteroidota ratio in the rumen.

关键词： Wheat silage Oaten hay Growth performance Nutrient digestibility Rumen fermentation Feedlot lamb

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Intelligent feedforward gust alleviation based on neural network

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Chinese Journal of Aeronautics 2024年第3期37卷 116-132页

作者： Yitao ZHOU Zhigang wu chao YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

This paper proposes a neural network-based intelligent feedforward gust alleviation framework,which includes a neural network identification model and a neural network controller.A neural network training dataset is formed by collecting flight data and the gust data encountered during the aircraft flight.A neural network identification model is first trained to accurately predict the aircraft’s ***,based on the output of the identification model and the collected flight data,the parameters of the time-delay neural network controller are obtained through a learning *** simulation results show that the designed intelligent controller has good gust alleviation effects for both continuous turbulence excitation and discrete gust *** example,when the aircraft is 40000 kg and the flight speed is 0.81Ma,the controller achieves a 67.82%reduction in wingtip acceleration and a 35.90%reduction in center of mass acceleration under continuous turbulence *** considering the measurement uncertainties,such as noise existing in the collected data,the trained controller can still achieve an acceptable gust alleviation ***,considering a flight in which the aircraft mass is constantly changing,the intelligent controller,which continuously learns from new flight data,maintains a good gust alleviation effect throughout the flight.

关键词： Gust alleviation Intelligent control Feedforward control Neural networks Time-varying aircraft

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Nonlinear aeroelastic analysis of a twin-tail boom UAV with rudder freeplay nonlinearities

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Chinese Journal of Aeronautics 2024年第9期37卷 276-296页

作者： Liuyue BAI Zhigang wu chao YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 10019lChina

The issue of nonlinear structural freeplays in aircraft has always been a significant *** study investigates the aeroelastic characteristics of a twin-tail boom Unmanned Aerial Vehicle(UAV)with simultaneous freeplay nonlinearity in its left and right rudders.A comprehen-sive Limit Cycle Oscillation(LCO)solution route is proposed for complex aircraft with multiple freeplays,which can consider both accuracy and *** the first time,this study reveals the unique LCO characteristics exhibited by twin-tail boom UAVs with rudder freeplays and pro-vides simulations and explanations of interesting phenomena observed during actual *** governing equations are established using the free-interface component mode synthesis method,and the LCOs of the system are mainly solved through the improved time-domain numerical con-tinuation method and frequency-domain numerical continuation ***,the study investigates the influence of the left and right rudder freeplay size ratio on the LCO *** results demonstrate that the twin-tail boom UAV exhibits two stable LCO types:close and dif-fering left and right rudder *** proposed method successfully describes the complete LCO behaviors of the ***,this study makes significant contributions to our understand-ing of the aeroelastic behavior of twin-tail boom UAVs with rudder freeplays.

关键词： Aeroelasticity Freeplay nonlinearity Limit cycle oscillation Numerical continuation Component mode synthesis

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Active flutter suppression of nonlinear fin-actuator system via inverse system and immersion and invariance method

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Chinese Journal of Aeronautics 2024年第4期37卷 343-362页

作者： Jin LU Zhigang wu chao YANG Chinese Aeronautical Establishment Beijing 100029China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Structural nonlinearities such as freeplay will affect the stability and even flight safety of the fin-actuator *** is a lack of a practical method for designing Active Flutter Suppression (AFS) control laws for nonlinear fin-actuator systems.A design method for the AFS controller of the nonlinear all-movable fin-electromechanical actuator system is established by combining the inverse system and the Immersion and Invariance (I&I) ***,the composite control law combining the inverse system principle and internal model control is used to offset the nonlinearity and dynamics of the actuator,so that its driving torque can follow the ideal ***,the ideal torque of the actuator is designed employing the I&I *** unfavorable oscillation of the fin is suppressed by making the output torque of the actuator track the ideal *** simulation results reveal that the proposed AFS method can increase the flutter speed of the nonlinear finactuator system with freeplay,and a set of controller parameters is also applicable for wider freeplay within a certain *** power required for the actuator does not exceed the power that can be provided by the commonly used aviation *** method can also resist a certain level of noise and external disturbance.

关键词： Aeroelasticity Active flutter suppression Fin-actuator system Freeplay Inverse system Immersion and invariance

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