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1Time-dependent categorization of volatile aroma compound formation in stewed Chinese spicy beef using electron nose profile coupled with thermal desorption GC–MS detection显示文摘In the present study,flavor profiles of Chinese spiced beef in the cooking process were comparatively analyzed by electronic nose,gas chromatography–mass spectrometry(GC–MS)with a thermal desorption system(TDS),and solid-phase microextraction(SPME).A total of 82 volatile compounds were identified,and 3-methyl-butanal,pentanal,hexanal,-xylene,heptanal,limonene,terpinene,octanal,linalool,4-terpinenol,-terpineol,and(E)-anethole were identified as the characteristic flavor compounds in Chinese spiced beef.Variation in the content of volatile components produced by different cooking processes was observed.In general,a cooking time of 4 h resulted in optimal flavor quality and stability.Results indicated that the electronic nose could profile and rapidly distinguish variation among different cooking time.The volatile profiling by TDS-GC–MS and responses from the electronic nose,in combination with multivariate statistical analysis,are a promising tool for control the cooking process of spiced beef.Hui Gong Zhen Yang Meng Liu Zhijia Shi Jiapeng Li Wenhua Chen Xiaoling Qiao 2017Food Science and Human Wellness2017,6,3:21
2Microstructure evolution of AZ91 alloy processed by a combination method of equal channel angular pressing and rolling显示文摘In the present work,AZ91 alloy was successfully processed by equal channel angular pressing(ECAP)for up to 16 passes and rolling(R)for multiple passes with a total reduction of 75%in addition to a combination method with ECAP plus rolling(ECAP+R).The effects of various processes(ECAP,R and ECAP+R)on microstructure evolution were analyzed and the influence of ECAP process on the rolling performance was examined.The result shows that ECAP contributed to a homogenous grain structure and formed a texture with higher Schmidt factors that was easy for rolling.A plate with smoother surface and reduced edge cracks was observed in the ECAP+R process than in the single R process.Although the microstructure of the alloy was similar after ECAP+R and R process,the sample of ECAP+R was more refined and had stronger second phase precipitation than the sample of R,which resulted in better rolling characteristics,along with the external surfaces.Qiong Xu Aibin Ma Yuhua Li Jiapeng Sun Yuchun Yuan Jinghua Jiang Chaoying Ni 2020Journal of Magnesium and Alloys2020,8,1:10
3Potential of multi-pass ECAP on improving the mechanical properties of a high-calcium-content Mg-Al-Ca-Mn alloy显示文摘In this study,the multi-pass equal channel angular pressing(ECAP)was employed on a high-calcium-content Mg-Al-Ca-Mn alloy to tailor its microstructure and mechanical properties.The obtained results showed that the network-shaped Mg2Ca and(Mg,Al)2Ca eutectic compounds in as-cast alloy were gradually crushed into ultra-fine particles after ECAP,which exhibited a bimodal particle size distribution and most aggregated at original grain boundaries.Dynamic recrystallization(DRX)of α-Mg occurred during hot deformation via a particle stimulated mechanism,and the almost complete DRX with an average grain size around 1.5μm was obtained after 12p-ECAP.Moreover,abundant nano-sized acicular and spherical precipitates were dynamically precipitated withinα-Mg grains during ECAP.Tensile test results indicated that the maximum strength and ductility were acquired for 12p-ECAP alloy with ultimate tensile strength of 372 MPa and fracture elongation of 8%.The enhanced strength of the alloy could be ascribed to fine DRX grains,ultra-fine Ca-containing particles and dynamically precipitated nano-precipitates,while the improved ductility was mainly due to the refined and homogeneous microstructure,and weak texture with high average Schmid factors.He Huang Huan Liu Ce Wang Jiapeng Sun Jing Bai Feng Xue Jinghua Jiang Aibin Ma 2019Journal of Magnesium and Alloys2019,7,4:10
4Spatial sampling of terahertz fields with sub-wavelength accuracy via probe-beam encoding显示文摘Recently,computational sampling methods have been implemented to spatially characterize terahertz(THz)fields.Previous methods usually rely on either specialized THz devices such as THz spatial light modulators or complicated systems requiring assistance from photon-excited free carriers with high-speed synchronization among multiple optical beams.Here,by spatially encoding an 800-nm near-infrared(NIR)probe beam through the use of an optical SLM,we demonstrate a simple sampling approach that can probe THz fields with a single-pixel camera.This design does not require any dedicated THz devices,semiconductors or nanofilms to modulate THz fields.Using computational algorithms,we successfully measure 128×128 field distributions with a 62-μm transverse spatial resolution,which is 15 times smaller than the central wavelength of the THz signal(940μm).Benefitting from the noninvasive nature of THz radiation and sub-wavelength resolution of our system,this simple approach can be used in applications such as biomedical sensing,inspection of flaws in industrial products,and so on.Jiapeng Zhao Yiwen E Kaia Williams Xi-Cheng Zhang Robert W.Boyd 2019Light(Science & Applications)2019,8,1:10
5A fnite element parametric modeling technique of aircraft wing structures显示文摘A fnite element parametric modeling method of aircraft wing structures is proposed in this paper because of time-consuming characteristics of fnite element analysis pre-processing.The main research is positioned during the preliminary design phase of aircraft structures.A knowledgedriven system of fast fnite element modeling is built.Based on this method,employing a template parametric technique,knowledge including design methods,rules,and expert experience in the process of modeling is encapsulated and a fnite element model is established automatically,which greatly improves the speed,accuracy,and standardization degree of modeling.Skeleton model,geometric mesh model,and fnite element model including fnite element mesh and property data are established on parametric description and automatic update.The outcomes of research show that the method settles a series of problems of parameter association and model update in the process of fnite element modeling which establishes a key technical basis for fnite element parametric analysis and optimization design.Tang Jiapeng Xi Ping Zhang Baoyuan Hu Bifu 2013Chinese Journal of Aeronautics2013,26,5:9
6Effect of proteolytic starter culture isolated from Chinese Dong fermented pork(Nanx Wudl)on microbiological,biochemical and organoleptic attributes in dry fermented sausages显示文摘The effect of a proteolytic starter culture isolated from Nanx Wudl,on microbiological,biochemical and organoleptic attributes of dry fermented sausages was investigated during processing.Based on preliminary screening,the combination of Staphylococcus xylosus SX16 and Lactobacillus plantarum CMRC6,showing excellent proteolytic activity in vitro,was selected as the multi-strain starter(starter LS).For comparison,the single-strain starter culture of L.plantarum CMRC6(starter LB)and non-inoculated control were also tested.During fermentation,lactic acid bacteria and staphylococci dominated the microbiota and suppressed the Enterobacteriaceae growth in LS-inoculated sausages.The addition of LS starter accelerated acidification and proteolysis during ripening,improving the contents of total free amino acids and several essential free amino acids(Phe,Ile and Leu).Volatile compounds analysis revealed that LS-fermented sausage showed the highest abundance of 3-methyl-1-butanol,probably due to the inoculated S.xylosus.The inoculation of LS starter improved the sensory properties of sausages,especially the flavor attribute.Therefore,S.xylosus SX16 and L.plantarum CMRC6 are promising candidates for inclusion as multi-strain starters in the manufacture of gourmet fermented dry sausage.Xi Chen Ruifang Mi Biao Qi Suyue Xiong Jiapeng Li Chao Qu Xiaoling Qiao Wenhua Chen Shouwei Wang 2021Food Science and Human Wellness2021,10,1:9
7Nitrated and parent PAHs in the surface water of Lake Taihu,China:Occurrence,distribution,source,and human health risk assessment显示文摘Nitrated polycyclic aromatic hydrocarbons(NPAHs)have toxic potentials that are higher than those of their corresponding parent polycyclic aromatic hydrocarbons(PAHs)and thus have received increasing attention in recent years.In this study,the occurrence,distribution,source,and human health risk assessment of 15 NPAHs and 16 PAHs were investigated in the surface water from 20 sampling sites of Lake Taihu during the dry,normal,and flood seasons of 2018.The PAH concentrations ranged from 255 to 7298 ng/L and the NPAH concentrations ranged from not-detected(ND)to 212 ng/L.Among the target analytes,2-nitrofluorene(2-n Flu)was the predominant NPAH,with a detection frequency ranging from 85%to 90%and a maximum concentration of 56.2 ng/L.The three-ringed and four-ringed NPAHs and PAHs comprised the majority of the detected compounds.In terms of seasonal variation,the highest levels of the NPAHs and PAHs were in the dry season and flood season,respectively.Diagnostic ratio analysis indicated that the prime source of NPAHs was direct combustion,whereas in the case of PAHs the contribution was predominantly from a mixed pattern including pollution from unburned petroleum and petroleum combustion.The human health risk of NPAHs and PAHs was evaluated using a lifetime carcinogenic risk assessment model.The carcinogenic risk level of the targets ranged from 2.09×10^(-7)to 5.75×10^(-5)and some surface water samples posed a potential health risk.Jijie Kong Yuxuan Dai Mengshu Han Huan He Jiapeng Hu Junyi Zhang Junzhe Shi Qiming Xian Shaogui Yang Cheng Sun 2021Journal of Environmental Sciences2021,33,4:6
8RBMDO Using Gaussian Mixture Model-Based Second-Order Mean-Value Saddlepoint Approximation显示文摘Actual engineering systems will be inevitably affected by uncertain factors.Thus,the Reliability-Based Multidisciplinary Design Optimization(RBMDO)has become a hotspot for recent research and application in complex engineering system design.The Second-Order/First-Order Mean-Value Saddlepoint Approximate(SOMVSA/-FOMVSA)are two popular reliability analysis strategies that are widely used in RBMDO.However,the SOMVSA method can only be used efficiently when the distribution of input variables is Gaussian distribution,which significantly limits its application.In this study,the Gaussian Mixture Model-based Second-Order Mean-Value Saddlepoint Approximation(GMM-SOMVSA)is introduced to tackle above problem.It is integrated with the Collaborative Optimization(CO)method to solve RBMDO problems.Furthermore,the formula and procedure of RBMDO using GMM-SOMVSA-Based CO(GMM-SOMVSA-CO)are proposed.Finally,an engineering example is given to show the application of the GMM-SOMVSA-CO method.Debiao Meng Shiyuan Yang Tao Lin Jiapeng Wang Hengfei Yang Zhiyuan Lv 2022Computer Modeling in Engineering & Sciences2022,,8:6
9Polyoxometalate-based silica-supported ionic liquids for heterogeneous oxidative desulfurization in fuels显示文摘With the aim of deep desulfurization, silica-supported polyoxometalate-based ionic liquids were successfully prepared by a one-pot hydrothermal process and employed in heterogeneous oxidative desulfurization of various sulfur compounds. The compositions and structures of the hybrid samples were characterized by various methods such as FT-IR, XPS, Raman,UV–Vis, wide-angle XRD and N_2 adsorption–desorption. The experimental results indicated that the hybrid materials presented a high dispersion of tungsten species and excellent catalytic activity for the removal of 4,6-dimethyldibenzothiophene without any organic solvent as extractant, and the sulfur removal could reach 100.0% under mild conditions.The catalytic performance on various substrates was also investigated in detail. After cycling seven cycles, the sulfur removal of the heterogeneous system still reached 93.0%. The GC-MS analysis results demonstrated that the sulfur compound was first adsorbed by the catalyst and subsequently oxidized to its corresponding sulfone.Ming Zhang Miao Wang Jiapeng Yang Hongping Li Jiaqi Liu Xiao Chen Wenshuai Zhu Huaming Li 2018Petroleum Science2018,15,4:5
10Cooperative and Competitive Multi-Agent Systems:From Optimization to Games显示文摘Multi-agent systems can solve scientific issues related to complex systems that are difficult or impossible for a single agent to solve through mutual collaboration and cooperation optimization.In a multi-agent system,agents with a certain degree of autonomy generate complex interactions due to the correlation and coordination,which is manifested as cooperative/competitive behavior.This survey focuses on multi-agent cooperative optimization and cooperative/non-cooperative games.Starting from cooperative optimization,the studies on distributed optimization and federated optimization are summarized.The survey mainly focuses on distributed online optimization and its application in privacy protection,and overviews federated optimization from the perspective of privacy protection me-chanisms.Then,cooperative games and non-cooperative games are introduced to expand the cooperative optimization problems from two aspects of minimizing global costs and minimizing individual costs,respectively.Multi-agent cooperative and non-cooperative behaviors are modeled by games from both static and dynamic aspects,according to whether each player can make decisions based on the information of other players.Finally,future directions for cooperative optimization,cooperative/non-cooperative games,and their applications are discussed.Jianrui Wang Yitian Hong Jiali Wang Jiapeng Xu Yang Tang Qing-Long Han Jürgen Kurths 2022IEEE/CAA Journal of Automatica Sinica2022,9,5:5
11Influence of Range Gate Width on Detection Probability and Ranging Accuracy of Single Photon Laser Altimetry Satellite显示文摘The influence of the single photon laser altimeter range-gate width on the detection probability and ranging accuracy is discussed and analyzed,according to the LiDAR equation,single photon detection equation and the Monte Carlo method to simulate the experiment.The simulated results show that the probability of detection is not affected by the range gate,while the probability of false alarm is relative to the gate width.When the gate width is 100 ns,the ranging accuracy can accord with the requirements of satellite laser altimeter.But when the range gate width exceeds 400 ns,ranging accuracy will decline sharply.The noise ratio will be more as long as the range gate to get larger,so the refined filtering algorithm during the data processing is important to extract the useful photons effectively.In order to ensure repeated observation of the same point for 25 times,we deduce the quantitative relation between the footprint size,footprint,and frequency repetition according to the parameters of ICESat-2.The related conclusions can provide some references for the design and the development of the domestic single photon laser altimetry satellite.Guoyuan LI Fanghong YE Xinming TANG Dongping XIE Jiapeng HUANG Genhua HUANG 2020Journal of Geodesy and Geoinformation Science2020,3,2:4
12Investigating the Effectiveness of Road-related Mitigation Measures under Semi-controlled Conditions:A Case Study on Asian Amphibians显示文摘Road traffic is the main factor causing the decline in amphibian populations worldwide. The proper design of an amphibian tunnel is one of the most efficient measures to mitigate the negative impacts of road traffic on amphibians. However, no study has investigated the effectiveness of amphibian tunnels under semi-controlled conditions in Asian amphibians. Here, we selected two representative amphibian species, the Chinese brown frog, Rana chensinensis, and the Asiatic toad, Bufo gargarizans, which suffer the most severe road mortality along the roads in Northeast China. We placed experimental arrays of culverts of various sizes(diameters of 1.5, 1, and 0.5 m for circular culverts; side lengths of 1.5, 1, and 0.5 m for box culverts), and substrate type(soil, concrete, and metal) to examine the preferences of both species during the migratory season between May and September in 2016 and 2017. The results revealed that the Chinese brown frog preferred mid-and large-sized culverts as well as soil culverts. We concluded that culverts with a side length ≥ 1 m, lined with soil, and accompanied by a ≥ 0.4 m high guide drift fence and ≤ 45° gradient on the roadside ditch wall would best facilitate road crossings for both species and likely for other amphibian species in Northeast China.Yun WANG Jiayu LAN Hongping ZHOU Lei GUAN Yudi WANG Yongshun HAN Jiapeng QU Syed Asifullah SHAH Yaping KONG 2019Asian Herpetological Research2019,10,1:4
132D MXene-Based Materials for Electrocatalysis显示文摘MXenes,as an emerging 2D material,are expected to exert a great influence on future energy storage and conversion technologies.In this review,we systematically summarize recent advances in MXene-based materials in electrocatalysis,particularly in the hydrogen evolution,oxygen evolution,oxygen reduction,nitrogen reduction,and CO2 reduction reactions.Crucial factors influencing the properties of these materials,such as functional groups,conductivity,and interface,are discussed,and challenges to the future development of MXene-based electrocatalysts are presented.Jiapeng Liu Wenchao Peng Yang Li Fengbao Zhang Xiaobin Fan 2020Transactions of Tianjin University2020,26,3:4
14Broadband mid-infrared supercontinuum generation in dispersion-engineered As_(2)S_(3)-silica nanospike waveguides pumped by 2.8 μm femtosecond laser显示文摘Broadband mid-infrared(IR)supercontinuum laser sources are essential for spectroscopy in the molecular fingerprint region.Here,we report generation of octave-spanning and coherent mid-IR supercontinua in As_(2)S_(3)-silica nanospike hybrid waveguides pumped by a custom-built 2.8μm femtosecond fiber laser.The waveguides are formed by pressure-assisted melt-filling of molten As_(2)S_(3) into silica capillaries,allowing the dispersion and nonlinearity to be precisely tailored.Continuous coherent spectra spanning from 1.1μm to 4.8μm(30 dB level)are observed when the waveguide is designed so that 2.8μm lies in the anomalous dispersion regime.Moreover,linearly tapered millimeter-scale As_(2)S_(3)-silica waveguides are fabricated and investigated for the first time,to the best of our knowledge,showing much broader supercontinua than uniform waveguides,with improved spectral coherence.The waveguides are demonstrated to be long-term stable and water-resistant due to the shielding of the As_(2)S_(3) by the fused silica sheath.They offer an alternative route to generating broadband mid-IR supercontinua,with applications in frequency metrology and molecular spectroscopy,especially in humid and aqueous environments.Pan Wang Jiapeng Huang Shangran Xie Johann Troles and Philip St.J.Russell 2021Photonics Research2021,9,4:4
15Enhanced production of seed oil with improved fatty acid composition by overexpressing NAD^(+)-dependent glycerol-3-phosphate dehydrogenase in soybean显示文摘There is growing interest in expanding the production of soybean oils(mainly triacylglycerol, or TAG) to meet rising feed demand and address global energy concerns. We report that a plastidlocalized glycerol-3-phosphate dehydrogenase(GPDH), encoded by GmGPDHp1 gene, catalyzes the formation of glycerol-3-phosphate(G3 P), an obligate substrate required for TAG biosynthesis.Overexpression of GmGPDHp1 increases soybean seed oil content with high levels of unsaturated fatty acids(FAs), especially oleic acid(C18:1), without detectably affecting growth or seed protein content or seed weight. Based on the lipidomic analyses, we found that the increase in G3 P content led to an elevated diacylglycerol(DAG) pool, in which the Kennedy pathwayderived DAG was mostly increased, followed by PC-derived DAG, thereby promoting the synthesis of TAG containing relatively high proportion of C18:1. The increased G3 P levels induced several transcriptional alterations of genes involved in the glycerolipid pathways. In particular, genes encoding the enzymes responsible for de novo glycerolipid synthesis were largely upregulated in the transgenic lines, in-line with the identified biochemical phenotype. These results reveal a key role for GmGPDHp1-mediated G3 P metabolism in enhancing TAG synthesis and demonstrate a strategy to modify the FA compositions of soybean oils for improved nutrition and biofuel.Ying Zhao Pan Cao Yifan Cui Dongxu Liu Jiapeng Li Yabin Zhao Siqi Yang Bo Zhang Runnan Zhou Minghao Sun Xuetian Guo Mingliang Yang Dawei Xin Zhanguo Zhang Xin Li Chen Lv Chunyan Liu Zhaoming Qi Jingyu Xu Xiaoxia Wu Qingshan Chen 2021Journal of Integrative Plant Biology2021,63,6:4
16Advancement of maxillary anterior segment by distraction osteogenesis for severe maxillary retrusion in cleft lip and palate显示文摘Gao Feng Yang Minlie Zhao Zhenmin Sun Xiaomei Yin Ningbei Wang Yongqian Song Tao Li Haidong Wu Di Yin Jiapeng Cao Yimei Tong Haizhou 2014Chinese Medical Journal2014,,3:4
17Predominant yeasts in Chinese Dong fermented pork(Nanx Wudl)and their aroma-producing properties in fermented sausage condition显示文摘Yeasts are one of the predominant microbial groups in fermented meats.In this study,yeast communities of Chinese Dong fermented pork(Nanx Wudl)were investigated and the technological properties of 73 yeast isolates were evaluated.Through culture-dependent and high-throughput sequencing methods,the main yeast species identified included Pichia membranifaciens,Kazachstania bulderi,Millerozyma farinosa,Candida zeylanoides,Kazachstania exigua,Candida parapsilosis and Saccharomyces cerevisiae.Among these yeasts,P.membranifaciens,M.farinosa,K.exigua and K.bulderi were detected in fermented meats for the first time.A total of 73 yeast isolates was investigated for their lipolytic and proteolytic activities.All yeast species showed lipolytic activity,while proteolytic activity against meat protein was only detected in S.cerevisiae.Assay of aroma-producing potential was performed in a model simulating fermented sausage condition.Inoculation of yeast strains increased volatiles production,especially esters and alcohols.The highest ester production was observed in S.cerevisiae Y70 strain,followed by K.exigua Y12 and K.bulderi Y19.C.zeylanoides Y10 and S.cerevisiae Y70 were the highest producers of benzeneethanol and 3-methyl-1-butanol.S.cerevisiae Y70 with its highest production of branched alcohols and esters could be a promising candidate as aroma enhancer in the manufacture of fermented sausages.Ruifang Mi Xi Chen Suyue Xiong Biao Qi Jiapeng Li Xiaoling Qiao Wenhua Chen Chao Qu Shouwei Wang 2021Food Science and Human Wellness2021,10,2:3
18Offering the win-win solutions between ecological conservation and livelihood development:National parks in Qinghai, China显示文摘National parks as protected areas have been on the spotlight because they are essential in achieving ecological civilization in China.Despite the profound achievements of national parks to conserve nature,the benefits of national parks for local residents remain lacking.Under the theory of harmonious coexistence between human and nature,this study focused on the development of local people’s livelihood in Qinghai’s national parks.We systematically explored the establishment of the national parks in Qinghai Province,analyzed the current prob-lems,and provided the main measures for developing people’s livelihood in protected areas in Qinghai.This study put forward the viewpoint that national parks should set a long-term goal,and gradually advance based on the environmental conditions and appropriately prioritize the improvement of local people’s wellbeing in the future.Qi Cheng Xue Cheng Kexin Ma Xinquan Zhao Jiapeng Qu 2020Geography and Sustainability2020,1,4:3
19Single-End Adaptive Optics Compensation for Emulated Turbulence in a Bi-Directional 10-Mbit/s per Channel Free-Space Quantum Communication Link Using Orbital-Angular-Momentum Encoding显示文摘A single-end adaptive-optics(AO)module is experimentally demonstrated to mitigate the emulated atmospheric turbulence efects in a bi-directional quantum communication link,which employs orbital angular momentum(OAM)for data encoding.A classical Gaussian beam is used as a probe to detect the turbulence-induced wavefront distortion in the forward direction of the link.Based on the detected wavefront distortion,an AO system located on one end of the link is used to simultaneously compensate for the forward and backward channels.Specifcally,with emulated turbulence and when the probe is turned on,the mode purity of photons carrying OAMℓ=1 is improved by∼21%with AO mitigation.We also measured the performance when encoding data using OAM{ℓ=−1,+2}and{ℓ=−2,+1}in the forward and backward channels,respectively,at 10 Mbit/s per channel with one photon per pulse on average.For this case,we found that the AO system could reduce the turbulence efects increased quantum-symbolerror-rate(QSER)by∼76%and∼74%,for both channels in the uni-directional and bi-directional cases,respectively.Similar QSER improvement is observed for the opposite direction channels in the bi-directional case.Cong Liu Kai Pang Zhe Zhao Peicheng Liao Runzhou Zhang Haoqian Song Yinwen Cao Jing Du Long Li Hao Song Yongxiong Ren Guodong Xie Yifan Zhao Jiapeng Zhao Seyed M.H.Rafsanjani Ari N.Willner Jeffrey H.Shapiro Robert W.Boyd Moshe Tur Alan E.Willner 2019Research2019,,1:3
20The N^6-adenine methylation in yeast genome profiled by single-molecule technology显示文摘The most common and abundant DNA modification is 5-methylcytosine(5mC),which has been well-established as an epigenetic mark regulating gene expression in eukaryotes(Jones,2012).Another DNA modification N^6-methyldeoxyadenosine(6mA),previously reported as a widespread DNA methylation in prokaryotes,Zhe Liang Guoliang Yu Jingrong Liu Yuke Geng Jinghui Mao Depeng Wang Jiapeng Zhou Xiaofeng Gu 2018Journal of Genetics and Genomics2018,45,4:3
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