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Dietary supplementation of benzoic acid and essential oils combination enhances intestinal resilience against LPS stimulation in weaned piglets 被引量:1
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作者 Chang Cui Yulong Wei +9 位作者 Yibo Wang Wen Ma xiaoyu zheng Jun Wang Ziwei Ma Caichi Wu Licui Chu Shihai Zhang Wutai Guan Fang Chen 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期878-897,共20页
Background The benefits of combining benzoic acid and essential oils(BAO)to mitigate intestinal impairment during the weaning process have been well established,while the detailed underlying mechanism has not been ful... Background The benefits of combining benzoic acid and essential oils(BAO)to mitigate intestinal impairment during the weaning process have been well established,while the detailed underlying mechanism has not been fully elucidated.Previous research has primarily focused on the reparative effects of BAO on intestinal injury,while neglecting its potential in enhancing intestinal stress resistance.Methods In this study,we investigated the pre-protective effect of BAO against LPS-induced stress using a modified experimental procedure.Piglets were pre-supplemented with BAO for 14 d,followed by a challenge with LPS or saline to collect blood and intestinal samples.Results Our findings demonstrated that BAO supplementation led to significant improvements in piglets’final weight,average daily gain,and feed intake/body gain ratio.Additionally,BAO supplementation positively influenced the composition of intestinal microbiota,increasing beneficial Actinobacteriota and Alloprevotella while reducing harmful Desulfobacterota,Prevotella and Oscillospira.Furthermore,BAO supplementation effectively mitigated oxidative disturbances and inflammatory responses induced by acute LPS challenge.This was evidenced by elevated levels of T-AOC,SOD,and GSH,as well as decreased levels of MDA,TNF-α,and IL-6 in the plasma.Moreover,piglets subjected to LPS challenge and pre-supplemented with BAO exhibited significant improvements in intestinal morphological structure and enhanced integrity,as indicated by restored expression levels of Occludin and Claudin-1 compared to the non-supplemented counterparts.Further analysis revealed that BAO supplementation enhanced the jejunal antioxidative capacity by increasing GSH-Px levels and decreasing MDA levels under the LPS challenge and stimulated the activation of the Nrf2 signaling pathway.Additionally,the reduction of TLR4/NF-κB/MAPK signaling pathways activation and proinflammatory factor were also observed in the jejunal of those piglets fed with BAO.Conclusions In summary,our study demonstrates that pre-supplementation of BAO enhances the anti-stress capacity of weaned piglets by improving intestinal microbiota composition,reinforcing the intestinal barrier,and enhancing antioxidative and anti-inflammatory capabilities.These effects are closely associated with the activation of Nrf2 and TLR4/NF-κB/MAPK signaling pathways. 展开更多
关键词 ANTI-STRESS Benzoic acid Essential oils INTESTINE LPS Weaned piglets
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A dynamic regulation of nitrogen on floret primordia development in wheat 被引量:1
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作者 Zhen Zhang Yujing Li +6 位作者 Yuxun Wu xiaoyu zheng Xiaolei Guo Wan Sun Zhencai Sun Zhimin Wang Yinghua Zhang 《The Crop Journal》 SCIE CSCD 2024年第1期271-280,共10页
Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilizati... Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilization is largely unknown.A high temporal-resolution investigation of floret primordia number and morphology,dry matter,and N availability was conducted under three N fertilization levels:0(N0),120(N1)and 240(N2)kg ha^(−1).Interestingly,fertile florets at anthesis stage were determined by those floret primordia with meiotic ability at booting stage:meiotic ability was a threshold that predicted whether a floret primordium became fertile or abortive florets.Because the developmental rate of the 4th floret primordium in the central spikelet was accelerated and then they acquired meiotic ability,the NFFs increased gradually as N application increased,but the increase range decreased under N2.There were no differences in spike N concentration among treatments,but leaf N concentration was increased in the N1 and N2 treatments.Correspondingly,dry matter accumulation and N content of the leaf and spike in the N1 and N2 treatments was increased as compared to N0.Clearly,optimal N fertilization increased leaf N availability and transport of assimilates to spikes,and allowed more floret primordia to acquire meiotic ability and become fertile florets,finally increasing NFFs.There was no difference in leaf N concentration between N1 and N2 treatment,whereas soil N concentration at 0–60 cm soil layers was higher in N2 than in N1 treatment,implying that there was still some N fertilization that remained unused.Therefore,improving the leaf’s ability to further use N fertilizer is vital for greater NFFs. 展开更多
关键词 Fertile florets Floret primordia Grain number Meiotic ability Morphological development
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Porcine enteric alphacoronavirus infection increases lipid droplet accumulation to facilitate the virus replication
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作者 Qi Gao Yongzhi Feng +7 位作者 Ting Gong Dongdong Wu xiaoyu zheng Yizhuo Luo Yunlong Yang Zebu Song Lang Gong Guihong Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期988-1005,共18页
Coronaviruses are widely transmissible between humans and animals, causing diseases of varying severity. Porcine enteric alphacoronavirus(PEAV) is a newly-discovered pathogenic porcine enteric coronavirus in recent ye... Coronaviruses are widely transmissible between humans and animals, causing diseases of varying severity. Porcine enteric alphacoronavirus(PEAV) is a newly-discovered pathogenic porcine enteric coronavirus in recent years, which causes watery diarrhea in newborn piglets. The host inflammatory responses to PEAV and its metabolic regulation mechanisms remain unclear, and no antiviral studies have been reported. Therefore, we investigated the pathogenic mechanism and antiviral drugs of PEAV. The transcriptomic analysis of PEAV-infected host cells revealed that PEAV could upregulate lipid metabolism pathways. In lipid metabolism, steady-state energy processes, which can be mediated by lipid droplets(LDs), are the main functions of organelles. LDs are also important in viral infection and inflammation. In infected cells, PEAV increased LD accumulation, upregulated NF-κB signaling, promoted the production of the inflammatory cytokines IL-1β and IL-8, and induced cell death. Inhibiting LD accumulation with a DGAT-1 inhibitor significantly inhibited PEAV replication, downregulated the NF-κB signaling pathway, reduced the production of IL-1β and IL-8, and inhibited cell death. The NF-κB signaling pathway inhibitor BAY11-7082 significantly inhibited LD accumulation and PEAV replication. Metformin hydrochloride also exerted anti-PEAV effects and significantly inhibited LD accumulation, downregulated the NF-κB signaling pathway, reduced the production of IL-1β and IL-8, and inhibited cell death. LD accumulation in the lipid metabolism pathway therefore plays an important role in the replication and pathogenesis of PEAV, and metformin hydrochloride inhibits LD accumulation and the inflammatory response to exert anti-PEAV activity and reducing pathological injury. These findings contribute new targets for developing treatments for PEAV infections. 展开更多
关键词 porcine enteric alphacoronavirus NF-κB inflammatory pathway lipid droplet metformin hydrochloride
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Activated carbon fibers with manganese dioxide coating for flexible fiber supercapacitors with high capacitive performance 被引量:3
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作者 Huifang Li Jiachen Liang +4 位作者 Huan Li xiaoyu zheng Ying Tao zheng-Hong Huang Quan-Hong Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第4期95-100,共6页
Fiber supercapacitor(FSC)is a promising power source for wearable/stretchable electronics and high capacitive performance of FSCs is highly desirable for practice flexible applications.Here,we report a composite of ma... Fiber supercapacitor(FSC)is a promising power source for wearable/stretchable electronics and high capacitive performance of FSCs is highly desirable for practice flexible applications.Here,we report a composite of manganese dioxide(Mn O_2)and activated carbon fibers(ACFs)with high MnO_2mass loading and microporous structure(abbreviated as Mn O_2@ACF),which is used as a fiber electrode to produce a FSC with a high capacitive performance and a good flexibility.The MnO_2@ACF composite electrode in FSCs delivers an ultrahigh specific capacitance of 410 mF/cm^2at 0.1 mA/cm^2,corresponding to a high energy density of 36μWh/cm^2and high power density of 726μW/cm^2.Such high capacitive performance and simple fabrication method indicates that the Mn O_2@ACF composite is a very promising electrode material for flexible fiber supercapacitors. 展开更多
关键词 Fiber SUPERCAPACITORS ACTIVATED carbon fibers MASS LOADING FLEXIBILITY
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Ultrafast Synthesis of Metal-Layered Hydroxides in a Dozen Seconds for High-Performance Aqueous Zn(Micro-)Battery 被引量:4
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作者 Xiangyang Li Fangshuai Chen +9 位作者 Bo Zhao Shaohua Zhang xiaoyu zheng Ying Wang Xuting Jin Chunlong Dai Jiaqi Wang Jing Xie Zhipan Zhang Yang Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第3期16-31,共16页
Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly re... Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly rely on traditional bottom-up method,which involves tedious steps,time-consuming treatments,or additional alkaline media,and is unfavorable for high-efficiency production.Herein,we present a facile,ultrafast and general avenue to synthesize transition metal hydroxides on carbon substrate within 13 s by Joule-heating method.With high reaction kinetics caused by the instantaneous high temperature,seven kinds of transition metal-layered hydroxides(TM-LDHs)are formed on carbon cloth.Therein,the fastest synthesis rate reaches~0.46 cm^(2)s^(-1).Density functional theory calculations further demonstrate the nucleation energy barriers and potential mechanism for the formation of metal-based hydroxides on carbon substrates.This efficient approach avoids the use of extra agents,multiple steps,and long production time and endows the LDHs@carbon cloth with outstanding flexibility and machinability,showing practical advantages in both common and micro-zinc ion-based energy storage devices.To prove its utility,as a cathode in rechargeable aqueous alkaline Zn(micro-)battery,the NiCo LDH@carbon cloth exhibits a high energy density,superior to most transition metal LDH materials reported so far. 展开更多
关键词 Ultrafast synthesis Thermal shock Metal-layered hydroxides Zn(micro-)battery
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Restored intestinal integrity,nutrients transporters,energy metabolism,antioxidative capacity and decreased harmful microbiota were associated with IUGR piglet's catch-up growth before weanling 被引量:2
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作者 Chang Cui Caichi Wu +7 位作者 Jun Wang Ziwei Ma xiaoyu zheng Pengwei Zhu Nuan Wang Yuhua Zhu Wutai Guan Fang Chen 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期390-408,共19页
Background:Intrauterine growth restriction(IUGR)is a major inducer of higher morbidity and mortality in the pig industry and catch-up growth(CUG)before weanling could significantly restore this negative influence.But ... Background:Intrauterine growth restriction(IUGR)is a major inducer of higher morbidity and mortality in the pig industry and catch-up growth(CUG)before weanling could significantly restore this negative influence.But there was limited knowledge about the underlying mechanism of CUG occurrence.Methods:Eighty litters of newborn piglets were divided into normal birth weight(NBW)and IUGR groups according to birth weight.At 26 d,those piglets with IUGR but over average body weight of eighty litters of weaned piglets were considered as CUG,and the piglets with IUGR still below average body weight were considered as NCUG.This study was conducted to systemically compare the intestinal difference among NBW,CUG and NCUG weaned piglets considering the crucial role of the intestine for piglet growth.Results:The results indicated that the m RNA expression of nutrients(amino acids,glucose,and fatty acids)transporters,and mitochondrial electron transport chain(ETC)I were upregulated in CUG piglets'gut with improved morphology compared with those NCUG,as well as the ratio of P-AMPK/AMPK protein expression which is the indicator of energy metabolism.Meanwhile,CUG piglet's gut showed higher antioxidative capacity with increased SOD and GSHPx activity,decreased MDA levels,as well as higher m RNA expressions of Nrf2,Keap1,SOD,and GSH-Px.Furthermore,inflammatory parameters including TNF-α,IL-1β,IL-6,and IL-12 factors,and the activation of MAPK and NF-κB signaling pathways were significantly elevated in the NCUG intestine,while the protein expression of ZO-1,Occludin and Claudin-1 was reduced.The alpha diversity of fecal microbiota was higher in CUG piglets in contrast with NCUG piglets,and the increased beneficial bacteria and decreased pathogenic bacteria was also observed in CUG piglets.Conclusions:CUG piglet's intestine showed comprehensive restoration including higher nutrients transport,energy metabolism,antioxidant capacity,and intestinal physical barrier,while lower oxidative stress,inflammatory response,and pathogenic microbiota. 展开更多
关键词 Antioxidative capacity Catch-up growth Gut Intrauterine growth retardation PIGLETS
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Ultrasound:The Potential Power for Cardiovascular Disease Therapy
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作者 xiaoyu zheng Qingyao Liao +7 位作者 Yue Wang Hua Li Xiaodong Wang Yaohui Wang Wentao Wu Junlin Wang Ling Xiao Jing Huang 《Cardiovascular Innovations and Applications》 2019年第B07期125-134,共10页
Ultrasound can be considered a mechanical wave for both clinical diagnostic and therapeutic purposes on the basis of its good penetrability and directivity while spreading in solid organs or tissues without any ionizi... Ultrasound can be considered a mechanical wave for both clinical diagnostic and therapeutic purposes on the basis of its good penetrability and directivity while spreading in solid organs or tissues without any ionizing radiation.As a powerful form of energy,ultrasound,is used for deep-tissue therapy with different sonication parameters.The feasibility of minimally invasive or noninvasive acoustic treatment of a variety of diseases,such as hypertension,arrhythmia,hypertrophic cardiomyopathy,and myocardial infraction,is being explored in animal experiments and clinical trials.In this review,we summarize the biomedical effects of acoustic intervention in experimental and clinical studies,current challenges,and the potential of ultrasound for cardiovascular disease therapy. 展开更多
关键词 ULTRASOUND CARDIOVASCULAR DISEASE THERAPY
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Plant essential oils combined with organic acids restored lipopolysaccharide-induced leaky intestine via gut microbial modulation in weaned piglets
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作者 xiaoyu zheng Yibo Wang +8 位作者 Xuemei Zhou Tanyi Deng Yueqi Zhao Zhichao Fu Yulong Wei Wen Ma Shihai Zhang Wutai Guan Fang Chen 《Animal Nutrition》 SCIE CAS CSCD 2024年第3期419-432,共14页
Intestine derived lipopolysaccharide(LPS)is closely related to systemic inflammation and disorders,yet little is known about its roles in the weanling stress of piglets and its potential as a nutritional intervention ... Intestine derived lipopolysaccharide(LPS)is closely related to systemic inflammation and disorders,yet little is known about its roles in the weanling stress of piglets and its potential as a nutritional intervention target.This study aimed to investigate the potential of essential oils(EO)and organic acids(OA)in mitigating weaning stress in piglets by modulating the circulation of intestine derived LPS.Seventy-two weaned piglets at 21 d old with body weight of 8.12±0.168 kg were randomly divided into a control group(CON)and an experimental group,each consisting of six pens with six piglets per pen,and were fed either a basal diet or a basal diet supplemented with 3 kg/t OA+500 g/t EO(EO+OA).On the 14th day of the feeding trial,12 weaned piglets were randomly selected from the CON group,and 6 piglets were selected from the experimental group.Based on diet composition and stress treatment,these 18 piglets were divided into the following three groups:1)CON group.Piglets were fed a basal diet and received an intraperitoneal injection of saline as a control.2)LPS group.Piglets were fed a basal diet and received an intraperitoneal injection of LPS(100μg/kg body weight)to induce stress.3)EO+OA+LPS group.Piglets were fed a basal diet supplemented with EO and OA and received an intraperitoneal injection of LPS(100μg/kg body weight)to induce stress.The results showed that EO+OA significantly ameliorated the oxidative imbalance and inflammation disorder induced by LPS in piglets'serum and intestine by inhibiting the activation of the Toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)/mitogen-activated protein kinase(MAPK)signaling pathway.Furthermore,compared to the LPS group,supplementation with EO+OA restored LPS-induced reductions in Bcl-2 protein expression in the piglets'intestines(P<0.05)and mitigated morphological damage;it also enhanced both the protein expression and relative gene expression of the tight junction proteins occludin and claudin-1(P<0.05),and reduced the plasma diamine oxidase activity(DAO)and LPS content(P<0.05).Compared to the CON group,supplementation with EO+OA altered the composition of the intestinal microbiota,increasing beneficial bacteria relative abundance(Faecalibacterium)(P<0.05)and decreasing harmful bacteria relative abundance[Rikenellaceae_RC9_gut_group(P<0.01),Negativibacillus(P<0.05)].Further analysis revealed that plasma LPS content in piglets was negatively correlated with the relative abundance of Faecalibacterium(r=−0.662,P=0.021),Akkermansia(r=−0.492,P=0.031),and average daily gain(ADG)(r=−0.912,P=0.041).Plasma LPS content was also positively correlated with the plasma inflammatory factors interleukin(IL)-1β(r=0.591,P=0.021),IL-6(r=0.623,P=0.021),IL-12(r=561,P=0.031)contents,and the relative abundance of Negativibacillus(r=0.712,P=0.041).In summary,the addition of EO+OA prevents the leakage of intestine derived LPS into the circulation by improving intestinal integrity and microbiota composition,thereby enhancing antioxidant and anti-inflammatory abilities and growth performance of weaned piglets. 展开更多
关键词 Weaned piglet Essential oil Organic acid Gut microbiota LIPOPOLYSACCHARIDE
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Evolution mechanism of lamellarαand interlayeredβduring hot compression of TC21 titanium alloy with a widmanst?tten structure 被引量:4
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作者 xiaoyu zheng Ke WANG +2 位作者 Cheng ZHANG Renlong XIN Qing LIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第3期475-483,共9页
TC21 titanium alloy,as an important metal to fabricate the aircraft structural components,has attracted great attentions recently.A TC21 titanium alloy with widmanst?tten structure was isothermally compressed.Based on... TC21 titanium alloy,as an important metal to fabricate the aircraft structural components,has attracted great attentions recently.A TC21 titanium alloy with widmanst?tten structure was isothermally compressed.Based on the microstructure observation,the evolution of initialβgrain,Grain Boundaryαphase(α;),lamellar a and interlayeredβwas systematically investigated.The results showed that,with the increasing of height reduction,theα;underwent an evolution process from bending/kinking to breaking inducing the corresponding blurring of initial coarse b grain outline.Meanwhile,a significant phase transformation from a to b took place at the terminations of brokenα;.The evolution of lamellarαand interlayeredβin the colony was closely related to their deformation compatibility.In the a colony,the interlayered b experienced a larger deformation amount than lamellarα.The higher distortion energy promoted the occurrence of Dynamic Recovery(DRV)and Dynamic Recrystallization(DRX)to generate many Low Angle Boundaries(LABs)and High Angle Boundaries(HABs)in interlayered b,which induced an apparent grain refinement of b phase.On the contrary,the lower distortion energy and low deformation temperature suppressed the occurrence of DRV/DRX and restrained the globularization of lamellarα.Furthermore,the microstructure observation clearly revealed that the shearing separation mechanism dominated the evolution of the a phase from lamellar to short bar-like morphology. 展开更多
关键词 Globularization Grain refinement Hot deformation Interlayeredβ Lamellarα Titanium alloy
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Spatially Interlinked Graphene with Uniformly Loaded Sulfur for High Performance Li-S Batteries 被引量:3
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作者 Donghai Liu Chen Zhang +4 位作者 Xiaohui Lv xiaoyu zheng Lei Zhang Linjie Zhi Quan-Hong Yang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2016年第1期41-45,共5页
Lithium-sulfur (Li-S) batteries have drawn extensive attentions due to their high energy density, environmental friendliness and low cost. In this study, three-dimensional (3D) graphene/S hybrid (G/S) is prepare... Lithium-sulfur (Li-S) batteries have drawn extensive attentions due to their high energy density, environmental friendliness and low cost. In this study, three-dimensional (3D) graphene/S hybrid (G/S) is prepared by a one-pot hydrothermal method together with redox reaction between S-based compound and graphene oxide (GO). G/S has a three dimensional porous structure, where graphene is interconnected with each other forming a 3D conductive network. It demonstrates that the pore structure of G/S can be well controlled by optimizing the drying method of the 3D graphene-based materials. Freeze drying and evaporation-induced drying can induce different density and pore structure of G/S. Electrochemical tests illustrate that the resulting hybrid can deliver a specific capacity of 891 mAh·g^-1 and 575 mAh·g^-1 for the 1^st and 100^th cycle at a current density of 500 mAh·g^-1 . 展开更多
关键词 Li-S battery GRAPHENE three-dimensional graphene/S hybrid different drying methods
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Daylight and thermal performance of a switchable ethylene tetra-fluoro-ethylene cushion with dynamic control in different climates 被引量:2
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作者 Wanfang Zhao Wei He +5 位作者 Zhongting Hu xiaoyu zheng Sheng Zhang Gaofei Xu Hongbing Chen Yanping Yuan 《Building Simulation》 SCIE EI CSCD 2022年第1期29-40,共12页
Switchable multi-layer ethylene tetra-fluoro-ethylene(ETFE)cushion controls the natural light and heat flux passing through the cushion with varying outdoor conditions by dynamically modifying its properties.In this p... Switchable multi-layer ethylene tetra-fluoro-ethylene(ETFE)cushion controls the natural light and heat flux passing through the cushion with varying outdoor conditions by dynamically modifying its properties.In this paper,the switchable ETFE cushions with ink printing of different optical and thermal properties were adopted as the window in a typical office model,and the indoor daylight and energy consumption were simulated by using Grasshopper software.Experimental model was built to validate the numerical model.Five locations representing five climate zones in China were selected to analyze the feasibility of the switchable ETFE cushion in different climates.The hourly indoor daylight and heat gain in a single day revealed the effects of the dynamic mechanism of ETFE cushion in improving indoor natural light and thermal environment.In addition,the annual daylight performance at the working area(1.5 m from the window)was simulated.ETFE cushion with printing of the lowest transmittance(ETFE1)was the optimal option for most cities and window-to-wall ratios,with the percentage of annual useful daylight hours up to 78.6%,except for the cases where the window-to-wall ratio(WWR)was 0.35 in Harbin,Beijing,and Hefei.The distribution of useful daylight hours revealed that ETFE cushions with low,medium,and high printing transmittance were suitable for offices where people work in the front,medium,and back region of the room,respectively.Energy consumption calculation revealed that ETFE1 showed advantages over other windows in most cities except for cities highly dominated by heating.ETFE1 delivered up to 33%of energy saving over a year in Kunming compared with the conventional double glazing but was not superior in cities with high heating and low cooling demands,such as Harbin. 展开更多
关键词 ethylene tetra-fluoro-ethylene(ETFE) useful daylight illuminance(UDI) energy consumption office building double glazing
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Heterogeneous synergistic catalysis by Ru-RuOx nanoparticles for Se-Se bond activation
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作者 Mu Lin Liqun Kang +12 位作者 Jun Gu Linxiu Dai Shengbo Tang Tao Zhang YuhaoWang Lindong Li xiaoyu zheng Wei Zhu Rui Si Xuefeng Fu Lingdong Sun Yawen Zhang Chunhua Yan 《Nano Research》 SCIE EI CAS CSCD 2017年第3期922-932,共11页
The transition from homogeneous to heterogeneous synthetic chemistry enabled by nanocatalysts necessitates investigations of the reaction mechanism and structure-activity relationships for inorganic nanoparticles and ... The transition from homogeneous to heterogeneous synthetic chemistry enabled by nanocatalysts necessitates investigations of the reaction mechanism and structure-activity relationships for inorganic nanoparticles and organic substrates. Herein, we report that hydrothermally synthesized ruthenium nano- particles performed differently in the Se--Se bond activation and selenylation of heterocydes, exhibiting a volcano-shaped relationship between catalytic activity and composition. A synergistic effect was observed for Ru-RuOx nanocatalysts, with numerous characterizations and density functional theory (DFT) calculations suggesting that a PhSeSePh molecule can initially be adsorbed on the metallic Ru sites and cleaved into two PhSe* species, which subsequently migrate to RuOx sites and react with the nucleophile to achieve the selenylation of heterocycles~ 展开更多
关键词 NANOPARTICLE RUTHENIUM SELENIUM heterogeneous catalysis synergistic effect
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TbF3 nanoparticles as dual-mode contrast agents for ultrahigh field magnetic resonance imaging and X-ray computed tomography
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作者 xiaoyu zheng Yanjie Wang +5 位作者 Lingdong Sun Naixiu Chen Lindong Li Shuo Shi Sivakumar Malaisamy Chunhua Yan 《Nano Research》 SCIE EI CAS CSCD 2016年第4期1135-1147,共13页
Considering the development of magnetic resonance imaging (MRI) under ultrahigh magnetic field (〉3 T), the exploration of novel contrast agents (CAs) for ultrahigh field MRI is urgently needed. Herein, we repor... Considering the development of magnetic resonance imaging (MRI) under ultrahigh magnetic field (〉3 T), the exploration of novel contrast agents (CAs) for ultrahigh field MRI is urgently needed. Herein, we report polyethyleneimine (PEI)-coated TbF3 nanoparticles (NPs), which were synthesized by a facile solvothermal method, as potential dual-mode CAs for ultrahigh field MRI and X-ray computed tomography (CT). Owing to their strong paramagnetism, the TbF3 NPs showed excellent transverse relaxivity (395.77 mM-l.s-1) and negligible longitudinal relaxivity under an ultrahigh magnetic field (7 T) with a great potential as a T2-weighted MRI contrast agent. Furthermore, by comparison with the clinically used CT CAs (iohexol), the TbF3 NPs showed superior X-ray attenuation ability. The practical application for T2-weighted MRI and CT imaging was demonstrated with an animal model. Moreover, cell cytotoxicity and in vivo toxicity assessments implied the low toxicity of TbF3 NPs. In summary the above results indicate that TbF3 NPs are promising candidates for ultrahigh field MRI and CT dual-mode imaging. 展开更多
关键词 NANOPARTICLE TbF3 magnetic resonance imaging (MRI) computed tomography(CT) contrast agent
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Analysis on Applicability Evaluation of Forensic Science Standards in China
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作者 Hejuan Jiao xiaoyu zheng +2 位作者 Yanbiao Zhao Feng Hua Hui zheng 《Journal of Forensic Science and Medicine》 2017年第4期203-209,共7页
Standard applicability is the ability of a standard to be suitable for the prescriptive purpose under specified conditions.There is no mature applicability.evaluation index system of standards worldwide at present.We ... Standard applicability is the ability of a standard to be suitable for the prescriptive purpose under specified conditions.There is no mature applicability.evaluation index system of standards worldwide at present.We aim to construct the index system for evaluating the applicability of forensic science standard.The index system of applicability evaluation is proposed using a statistical analysis on the applicability of forensic science standards in China.We summarize the major problems and reasons in developing and revising the national and industry standards in China.Based on these,we put forward measures to improve standards’applicability,provide policy support for rectifying the standards,and lay the theoretical foundation for the construction,adjustment,and optimization of the forensic science standard system. 展开更多
关键词 Applicability evaluation forensic science STANDARD STANDARDIZATION
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