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Interface Engineering of Titanium Nitride Nanotube Composites for Excellent Microwave Absorption at Elevated Temperature

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Nano-Micro Letters 2024年第9期16卷 147-160页

作者： Cuiping Li Dan Li Shuai Zhang Long Ma Lei Zhang* Jingwei Zhang Chunhong Gong College of Chemistry and Molecular sciences Henan UniversityKaifeng 475004People’s Republic of China national and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004People’s Republic of China

Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently,the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority.Herein,due to the high melting point,good electrical conductivity,excellent environmental stability,EM coupling effect,and abundant interfaces of titanium nitride(TiN)nanotubes,they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process.Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane(PDMS),enhanced polarization loss relaxations were created,which could not only improve the depletion efficiency of EMWA,but also contribute to the optimized impedance matching at elevated temperature.Therefore,the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature(298-573 K),while achieved an effective absorption bandwidth(EAB)value of 3.23 GHz and a minimum reflection loss(RLmin)value of−44.15 dB at 423 K.This study not only clarifies the relationship between dielectric loss capacity(conduction loss and polarization loss)and temperature,but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering.

关键词： TiN nanotubes Interface engineering Polarization loss Impedance matching Electromagnetic wave absorption performance

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Effects of Enteromorpha prolifera polysaccharides on growth performance,intestinal barrier function and cecal microbiota in yellow-feathered broilers under heat stress

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Journal of Animal science and Biotechnology 2024年第1期15卷 344-361页

作者： Wenchao Liu Huimei Liu Yaoyao Wang Zhongxiang Zhao Balamuralikrishnan Balasubramanian Rajesh Jha Department of Animal science College of Coastal Agricultural SciencesGuangdong Ocean UniversityZhanjiangGuangdong 524088People’s Republic of China Department of Food science and Biotechnology College of Life ScienceSejong UniversitySeoul 05006South Korea Department of Human Nutrition Food and Animal SciencesCollege of Tropical Agriculture and Human ResourcesUniversity of Hawaii at ManoaHonoluluHI 96822USA

Background Global warming leading to heat stress(HS)is becoming a major challenge for broiler production.This study aimed to explore the protective effects of seaweed(Enteromorpha prolifera)polysaccharides(EPS)on the intestinal barrier function,microbial ecology,and performance of broilers under HS.A total of 144 yellow-feathered broilers(male,56 days old)with 682.59±7.38 g were randomly assigned to 3 groups:1)TN(thermal neutral zone,23.6±1.8℃),2)HS(heat stress,33.2±1.5℃ for 10 h/d),and 3)HSE(HS+0.1%EPS).Each group contained 6 replicates with 8 broilers per replicate.The study was conducted for 4 weeks;feed intake and body weights were measured at the end of weeks 2 and 4.At the end of the feeding trial,small intestine samples were collected for histomorphology,antioxidant,secretory immunoglobulin A(s Ig A)content,apoptosis,gene and protein expression analysis;cecal contents were also collected for microbiota analysis based on 16S r DNA sequencing.Results Dietary EPS promoted the average daily gain(ADG)of broilers during 3–4 weeks of HS(P<0.05).At the end of HS on broilers,the activity of total superoxide dismutase(T-SOD),glutathione S-transferase(GST),and the content of s Ig A in jejunum were improved by EPS supplementation(P<0.05).Besides,dietary EPS reduced the epithelial cell apoptosis of jejunum and ileum in heat-stressed broilers(P<0.05).Addition of EPS in HS group broilers'diet upregulated the relative m RNA expression of Occludin,ZO-1,γ-GCLc and IL-10 of the jejunum(P<0.05),whereas downregulated the relative m RNA expression of NF-κB p65,TNF-αand IL-1βof the jejunum(P<0.05).Dietary EPS increased the protein expression of Occludin and ZO-1,whereas it reduced the protein expression of NF-κB p65 and MLCK(P<0.01)and tended to decrease the protein expression of TNF-α(P=0.094)in heat-stressed broilers.Furthermore,the proportions of Bacteroides and Oscillospira among the three groups were positively associated with jejunal apoptosis and pro-inflammatory cytokine expression(P<0.05)and negatively correlated with j

关键词： Broilers Cecal microbiota Heat stress Intestinal barrier function Seaweed polysaccharides

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Production of Functional Materials Derived from Regenerated Silk Fibroin by Utilizing 3D Printing and Biomimetic Enzyme-induced Mineralization

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Chinese Journal of Polymer science 2024年第3期42卷 299-310,I0005页

作者： Ni Chen Fei-Yu Luo Gong-Wen Yang Jin-Rong Yao Xin Chen Zheng-Zhong Shao State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced Materials and Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique,integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase(ALP), was developed. Initially,a pre-cured hydrogel of regenerated silk fibroin(RSF) with a small quantity of hydroxypropyl cellulose(HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate(Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization process.Moreover, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures.

关键词： Silk protein Alkaline phosphatase Extrusion-based printing Biomineralization

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DLP:towards active defense against backdoor attacks with decoupled learning process

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Cybersecurity 2024年第1期7卷 122-134页

作者： Zonghao Ying Bin Wu State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijingChina School of Cyber Security University of Chinese Academy of SciencesBeijingChina

Deep learning models are well known to be susceptible to backdoor attack,where the attacker only needs to provide a tampered dataset on which the triggers are injected.Models trained on the dataset will passively implant the backdoor,and triggers on the input can mislead the models during testing.Our study shows that the model shows different learning behaviors in clean and poisoned subsets during training.Based on this observation,we propose a general training pipeline to defend against backdoor attacks actively.Benign models can be trained from the unreli-able dataset by decoupling the learning process into three stages,i.e.,supervised learning,active unlearning,and active semi-supervised fine-tuning.The effectiveness of our approach has been shown in numerous experiments across various backdoor attacks and datasets.

关键词： Deep learning Backdoor attack Active defense

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Distributed Stochastic Scheduling of Massive Backup Batteries in Cellular Networks for Operational Reserve and Frequency Support Ancillary Services

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 393-404页

作者： Kun Li Jiakun Fang Xiaomeng Ai Shichang Cui Rongkang Zhao Jinyu Wen State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China IEEE

Base station(BS)backup batteries(BSBBs),with their dispatchable capacity,are potential demand-side resources for future power systems.To enhance the power supply reliability and post-contingency frequency security of power systems,we propose a two-stage stochastic unit commitment(UC)model incorporating operational reserve and post-contingency frequency support provisions from massive BSBBs in cellular networks,in which the minimum backup energy demand is considered to ensure BS power supply reliability.The energy,operational reserve,and frequency support ancillary services are co-optimized to handle the power balance and post-contingency frequency security in both forecasted and stochastic variable renewable energy(VRE)scenarios.Furthermore,we propose a dedicated and scalable distributed optimization framework to enable autonomous optimizations for both dispatching center(DC)and BSBBs.The BS model parameters are stored and processed locally,while only the values of BS decision variables are required to upload to DC under the proposed distributed optimization framework,which safeguards BS privacy effectively.Case studies on a modified IEEE 14-bus system demonstrate the effectiveness of the proposed method in promoting VRE accommodation,ensuring post-contingency frequency security,enhancing operational economics,and fully utilizing BSBBs'energy and power capacity.Besides,the proposed distributed optimization framework has been validated to converge to a feasible solution with near-optimal performance within limited iterations.Additionally,numerical results on the Guangdong 500 kV provincial power system in china verify the scalability and practicality of the proposed distributed optimization framework.

关键词： Base station backup battery operational reserve frequency security distributed optimization privacy

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Study of the multi-physics field-coupled model of the two-stage electrostatic precipitator

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Building Simulation 2024年第3期17卷 387-398页

作者： Wenjia Hao Yu Guo Yukun Wang Tao Yu Hao Gao Zhengwei Long Tianjin Key Laboratory of Indoor Air Environmental Quality Control School of Environmental Science and EngineeringTianjin UniversityWeijin Road 92Tianjin300072China Wuhan Second Ship Design and Research Institute WuhanChin

The two-stage electrostatic precipitator is widely used to purify oil mist particles.However,there is limited research on the influences of relative humidity,particle deposition characteristics,and the generation of gaseous pollutants.Therefore,this paper established a numerical model of the electrostatic oil mist purifier and applied it to a two-stage electrostatic precipitator.Then the model was used to investigate the corona discharge characteristics under different relative humidity conditions in the charged zone,the particle deposition characteristics,the purification efficiency,the ozone concentration distribution,and the oil vapor concentration distribution in the collection zone.The results indicate that,with a constant temperature,the corona current decreases as relative humidity increase,and there is a quadratic relationship between relative humidity and current.The variation in relative humidity has little impact on the purification efficiency.The maximum ozone concentration occurs near the electrode line,and its concentration is influenced by the discharge current and inlet airflow velocity.The oil vapor concentration reaches its maximum value at the side plates,with a value of 19 ppb,while it reaches the minimum value at the collecting zone electrode plate,with a value of 2 ppb.The temperature is the main factor affecting the volatilization of the oil film,with higher temperatures resulting in higher oil vapor.

关键词： two-stage ESPs particle deposition corona discharge oil vapor

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Uncertainty and disturbance estimator-based model predictive control for wet flue gas desulphurization system

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Chinese Journal of Chemical Engineering 2024年第3期67卷 182-194页

作者： Shan Liu Wenqi Zhong Li Sun Xi Chen Rafal Madonski School of Energy and Environment Key Laboratory of Energy Thermal Conversion and Control of Ministry of EducationSoutheast UniversityNanjing 210096China Faculty of Automatic Control Electronics and Computer ScienceSilesian University of TechnologyGliwise 44-100Poland

Wet flue gas desulphurization technology is widely used in the industrial process for its capability of efficient pollution removal.The desulphurization control system,however,is subjected to complex reaction mechanisms and severe disturbances,which make for it difficult to achieve certain practically relevant control goals including emission and economic performances as well as system robustness.To address these challenges,a new robust control scheme based on uncertainty and disturbance estimator(UDE)and model predictive control(MPC)is proposed in this paper.The UDE is used to estimate and dynamically compensate acting disturbances,whereas MPC is deployed for optimal feedback regulation of the resultant dynamics.By viewing the system nonlinearities and unknown dynamics as disturbances,the proposed control framework allows to locally treat the considered nonlinear plant as a linear one.The obtained simulation results confirm that the utilization of UDE makes the tracking error negligibly small,even in the presence of unmodeled dynamics.In the conducted comparison study,the introduced control scheme outperforms both the standard MPC and PID(proportional-integral-derivative)control strategies in terms of transient performance and robustness.Furthermore,the results reveal that a lowpass-filter time constant has a significant effect on the robustness and the convergence range of the tracking error.

关键词： Desulphurization system Disturbance rejection Model predictive control Uncertainty and disturbance estimator Nonlinear system

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Significantly enhanced thermal stability of HMX by phase-transition lysozyme coating

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Defence Technology（防务技术） 2024年第5期35卷 60-68页

作者： Jiahui Liu Congmei Lin Jianhu Zhang Chengcheng Zeng Zhijian Yang Fude Nie Institute of Chemical Materials China Academy of Engineering Physics(CAEP)Mianyang 621900China Graduate School China Academy of Engineering Physics(CAEP)Mianyang 621900China

A new robust bio-inspired route by using lysozyme aqueous solution for surface modification on 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)was described in this paper.HMX crystals were coated by in situ phase transition of lysozyme(PTL)molecules.The HMX decorated by PTL was characterized by SEM,XRD,FTIR and XPS,demonstrating a dense core-shell coating layer.The coverage of lysozyme on HMX crystal was calculated by the ratio of sulfur content.The surface coverage increased from 60.5% to 93.5% when the content of PTL was changed from 0.5 wt% to 2.0 wt%,indicating efficient coating.The thermal stability of HMX was investigated by in situ XRD and DSC.The thermal phase transition temperature of HMX(β to δ phase)was delayed by 42℃ with 2.0 wt% PTL coating,which prevented HMX from thermal damage and sensitivity by the effect of PTL coating.After heating at 215℃,large cracks appeared in the naked HMX crystal,while the PTL coated HMX still maintained intact,with the impact energy of HMX dropped dramatically from 5 J to 2 J.However,the impact energy of HMX with 1.0 wt% and 2.0 wt% coating content(HMX@PTL-1.0 and HMX@PTL-2.0)was unchanged(5 J).Present results potentially enable large-scale fabrication of polymorphic energetic materials with outstanding thermal stability by novel lysozyme coating.

关键词： HMX Lysozyme Phase transition Thermal stability Sensitivity

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Reynolds-number scaling analysis on lift generation of a flapping and passive rotating wing with an inhomogeneous mass distribution

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Chinese Journal of Aeronautics 2024年第2期37卷 259-269页

作者： Suyang QIN Haotian HANG Yang XIANG Hong LIU J.C.Wu center for aerodynamics school of aeronautics and astronauticsshanghai jiao tong universityshanghai 200240china

Insects usually fly by passively rotating wings,which has been applied to the design of flapping-wing Micro-Air Vehicles(MAVs)to reduce mechanical complexity.In this paper,a robotic passive rotating-wing model is designed to investigate wing kinematics and lift generation,which are measured by a high-speed camera and a force transducer,respectively.In addition,flow fields are measured using the Particle Image Velocimetry(PIV).Experimental results demonstrate that passive rotating motion has a coordinative relationship with actively stroking motion.As the stroke amplitude or frequency increases,the rotating amplitude is enlarged.To characterize the active stroking motion,a driving Reynolds number Redrivingis defined,which varies from 68 to 366 in this study.Moving the gravity center of the wing towards trailing ed ge induces the increase of additional torque M,which decreases the wing rotating amplitude and promotes the advance of wing rotation.We find that the timing of wing rotation is gradually delayed and the mean lift coefficient C^(-)_(L)monotonously decreases as Redrivingincreases.By increasing the additional torque M,C^(-)_(L)is slightly improved and approaches to the lift coefficient of a real fruit fly at driving Re approximately equal to 230.The instantaneous lifts combined with the vortical structures further demonstrate that the lift generation associated with wing rotation is mainly attributed to the growth of the LeadingEdge Vortex(LEV)and the passive wake capture mechanism.Passive wake capture is influenced by LEV,reversal stroke motion and wing additional torque together,which can only maintain the lift at a high level for a considerable period.The high-lift generation mechanisms of flapping and passive rotating flight could shed light on the simplified design of MAVs and the improvement of their aerodynamic performance.

关键词： Flapping flight Unsteady lift Passive rotation Vortex flow Leading-edge vortex

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Lactate:a prospective target for therapeutic intervention in psychiatric disease

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Neural Regeneration Research 2024年第7期19卷 1473-1479页

作者： Yanhui Cai Haiyun Guo Tianle Han Huaning Wang Department of Psychiatry Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Anesthesiology and Perioperative Medicine Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina

Although antipsychotics that act via monoaminergic neurotransmitter modulation have considera ble therapeutic effect,they cannot completely relieve clinical symptoms in patients suffering from psychiatric disorde rs.This may be attributed to the limited range of neurotransmitters that are regulated by psychotropic drugs.Recent findings indicate the need for investigation of psychotropic medications that target less-studied neurotransmitte rs.Among these candidate neurotransmitters,lactate is developing from being a waste metabolite to a glial-neuronal signaling molecule in recent years.Previous studies have suggested that cerebral lactate levels change considerably in numerous psychiatric illnesses;animal experiments have also shown that the supply of exogenous la ctate exerts an antidepressant effect.In this review,we have described how medications targeting newer neurotransmitte rs offer promise in psychiatric diseases;we have also summarized the advances in the use of lactate(and its corresponding signaling pathways)as a signaling molecule.In addition,we have described the alterations in brain lactate levels in depression,anxiety,bipolar disorder,and schizophrenia and have indicated the challenges that need to be overcome before brain lactate can be used as a therapeutic target in psychopharmacology.

关键词： antidepressant anxiety bipolar disorder depression lactate psychiatric disease psychopharmacology schizophrenia signal molecular therapeutics

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