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液质联用法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素

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粮食与油脂 2024年第8期37卷 146-150页

作者：黄忠亮王海波廖强李琬婧吴张静覃弘毅广西壮族自治区医疗器械检测中心广西南宁530031 广西-东盟食品检验检测中心广西南宁530029 广西壮族自治区食品药品审评查验中心广西南宁530029 南宁市食品药品检验所广西南宁530000

建立液相色谱-串联质谱法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素的方法。样品经乙腈-水溶液(体积比6:4)提取,再利用一步法快速净化柱(QMyco-Multi)在自动固相萃取仪上完成快速净化,最后通过液相色谱分离,在电喷雾离子源(E... 详细信息

建立液相色谱-串联质谱法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素的方法。样品经乙腈-水溶液(体积比6:4)提取,再利用一步法快速净化柱(QMyco-Multi)在自动固相萃取仪上完成快速净化,最后通过液相色谱分离,在电喷雾离子源(ESI)正负离子模式下同时进行多重反应离子监测(MRM)。结果表明:14种真菌毒素在不同质量浓度范围内线性关系良好(相关系数>0.99),定量限为0.2~10.0μg/kg,加标回收率为81%~117%,相对标准偏差(RSD)为2.0%~7.2%(n=6)。制备的方法简单快速、灵敏准确,可用于药食同源杂粮中14种真菌毒素的同时测定。

关键词：药食同源杂粮真菌毒素一步法快速净化自动固相萃取

To improve robustness of mechanical properties of semi-solid cast A356 alloy using taguchi design method

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China Foundry 2024年第2期21卷 175-184页

作者： yi-wu Xu hong-yi Zhan Wei Tong Jin-ping Li Le-peng Zhang De-jiang Li Xiao-qin Zeng School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China China Science Lab General Motors Global Research&DevelopmentShanghai 201206China General Motors(China)Investment Co. Ltd.Shanghai 201206China China International Intellectech Corporation(CIIC) Beijing 100004China

Mechanical properties of semi-solid casting are dependent on multiple processing parameters,and improper processing parameters will not only reduce mean data but also increase *** present study investigated the impact of parameters in slurry preparation and heat treatment on the yield strength and ductility of T6 heat-treated A356 Al-Si alloy using rapid slurry forming(RSF)semi-solid *** focus was primarily on the robustness of mechanical properties based on Taguchi design *** analyzing signal-to-noise ratio and minimum value calculated from-3S,the optimum slurry preparation parameters and heat treatment parameters were determined to be no quench,enthalpy exchange material(EEM)temperature of 140℃,EEM-to-melt ratio of 6mass%,stirring time of 18 s,solution heat treated at 520℃ for 2 h,and ageing heat treated at 190℃ for 6 *** a small batch validation,the-3S yield strength and-3S elongation reach 256.1 MPa and 5.03% respectively,showing a satisfactory *** hardness and microstructure of heat-treated samples with the best and worst properties were characterized to gain insight into the underlying mechanisms affecting the mean value and variations of mechanical properties.

关键词： semi-solid casting taguchi design method signal-to-noise ratio mechanical property microstructure

Effect of the yaw angle on turbulent flow structures around the submarine model

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Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： yi-jing Hu yi Qu qin Wu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of Electronic System Engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

MicroR-9c-5p and novel-mir50 co-target Akt to regulate Lasioderma serricorne reproduction

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Insect Science 2024年第1期31卷 106-118页

作者： yi Yan Dong-Dong qin hong Yang Kang-Kang Xu Can Li Wen-Jia Yang Provincial Key Laboratory for Agricultural Pest Management of Mountainous Region Institute of EntomologyGuizhou UniversityGuiyangChina Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region College of Biology and Environmental EngineeringGuiyang UniversityGuiyangChina

High fecundity is a common characteristic of insect pests which increases the difficulty of population ***/threonine kinase Akt is an indispensable component of the insulin signaling *** of LsAkt severely hinders reproduction in Lasioderma serricorne,a stored product insect ***,the post-transcriptional pathway of LsAkt in *** remains *** study identified 2 binding sites of miR-9c-5p and novel-mir50 in the coding sequences of *** expression profiles of 2 microRNAs(miRNAs)and LsAkt displayed an opposite pattern during the adult *** reporter assay showed that novel-mir50 and miR-9c-5p could downregulate the expression of *** of miR-9c-5p and novel-mir50 by injection of mimics inhibited the expression of LsAkt and reduced oviposition,decreased egg hatchability,and blocked ovarian *** also decreased the expression of genes involved in ovarian development(LsVg and LsVgR)and the nutritional signaling pathway(LsTOR,LsS6K,and Ls4EBP),and reduced the phosphorylation of ***,injection of miR-9c-5p and novel-mir50 inhibitors induced the expressions of LsAkt,LsVg,LsVgR,LsTOR,LsS6K,and Ls4EBP,enhanced Akt phosphorylation level,and accelerated ovarian *** of bovine insulin downregulated the expression of miR-9c-5p and novel-mir50 and upregulated the LsAkt *** also rescued the reproductive development defects associated with miR-9c-5p/novel-mir50 overexpression,forming a positive regulatory loop of insulin *** results indicate that miR-9c-5p/novel-mir50 regulates the female reproduction of *** by targeting Akt in response to insulin *** data also demonstrate the effects of the insulin/miRNA/Akt regulatory axis in insect reproduction.

关键词： Akt insulin Lasioderma serricorne microRNA reproduction

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 *** 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,*** 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 *** the stroke amplitude or frequency increases,the rotating amplitude is *** characterize the active stroking motion,a driving Reynolds number Redrivingis defined,which varies from 68 to 366 in this *** 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 *** find that the timing of wing rotation is gradually delayed and the mean lift coefficient C^(-)_(L)monotonously decreases as *** 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 *** 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 *** 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 *** 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

Large-field objective lens for multi-wavelength microscopy at mesoscale and submicron resolution

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Opto-Electronic Advances 2024年第6期7卷 41-56页

作者： Xin Xu qin Luo Jixiang Wang Yahui Song hong Ye Xin Zhang yi He Minxuan Sun Ruobing Zhang Guohua Shi School of Biomedical Engineering(Suzhou) Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230026China Jiangsu Key Laboratory of Medical Optics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of ScienceSuzhou 215163China

Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view,typically around 1 *** restriction poses a challenge when attempting to simultaneously analyze various parts of a sample,such as different brain *** addition,conventional objective lenses struggle to perform consistently across the required range of wavelengths for brain imaging in *** we present a novel mesoscopic objective lens with an impressive field of view of 8 mm,a numerical aperture of 0.5,and a working wavelength range from 400 to 1000 *** achieved a resolution of 0.74μm in fluorescent beads *** versatility of this lens was further demonstrated through high-quality images of mouse brain and kidney sections in a wide-field imaging system,a confocal laser scanning system,and a two-photon imaging *** mesoscopic objective lens holds immense promise for advancing multi-wavelength imaging of large fields of view at high resolution.

关键词： mesoscopic objective lens large field-of-view high resolution multi-wavelength wide-field microscopy confocal laser scanning microscopy

Construction of Optimal Mixed-Level Uniform Designs

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Journal of Systems Science & Complexity 2024年第2期37卷 841-862页

作者： CHATTERJEE Kashinath LIU Min-Qian qin hong YANG Liuqing Department of Population Health Sciences Division of Biostatistics and Data ScienceAugusta UniversityGA 30912USA NITFID LPMC&KLMDASRSchool of Statistics and Data ScienceNankai UniversityTianjin 300071China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073China

The theory of uniform design has received increasing interest because of its wide application in the field of computer *** generalized discrete discrepancy is proposed to evaluate the uniformity of the mixed-level factorial *** this paper,the authors give a lower bound of the generalized discrete discrepancy and provide some construction methods of optimal mixed-level uniform designs which can achieve this lower *** methods are all deterministic construction methods which can avoid the complexity of stochastic *** saturated mixed-level uniform designs and supersaturated mixed-level uniform designs can be obtained with these ***,the resulting designs are also χ^(2)-optimal and minimum moment aberration designs.

关键词： Generalized discrete discrepancy Hadamard matrix mixed-level design orthogonal array supersaturated design

Hematite-facilitated microbial ammoxidation for enhanced nitrogen removal in constructed wetlands

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 35-45页

作者： Hao qin Wenbo Nie Duo yi Dongxu Yang Mengli Chen Tao Liu yi Chen Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment(Ministry of Education) Chongqing UniversityChongqing 400045China College of Environment and Ecology Chongqing UniversityChongqing 400045China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 610031China

Constructed wetlands(CWs)are widely applied for decentralized wastewater ***,achieving efficient removal of ammonia(NH+-N)has proven challenging due to insufficient *** this study,natural hematite(Fe,O3)was employed as a CW substrate(H-CWs)for the first time to drive anaerobic ammonia oxidation coupled with iron(I)reduction(Feammox).Compared to gravel constructed wetlands(G-CWs),ammonia removal was enhanced by 38.14%to 54.03%and nitrous oxide(N_(2)0)emissions were reduced by 34.60%in *** synergistic removal of ammonia and nitrate by H-CWs also resulted in the absence of ammoxidation *** and 15N isotope tracer incubations showed that Feammox accounting for approximately 40%of all ammonia removal in the *** enrichment of iron phosphate(Fe_(3)Fe_(4)(PO_(4))_(6))promoted the accumulation of the Feammox intermediate compound *** nanowires were observed on the surface of H-CW substrates as well,suggesting that the observed biological ammoxidation was most likely related to extracellular electron transfer(EET).Microbial and metagenomics analysis revealed that H-CWs elevated the integrity and enhanced the abundance of functional microorganisms and genes associated with nitrogen ***,the efficient ammonia removal in the absence of O2 together with a reduction in N_(2)O emissions as described in this study may provide useful guidance for hematite-mediated anaerobic ammonia removal in CWs.

关键词： Constructed wetlands Nitrogen removal Feammox Hematite Iron cycle

Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： yi-Lang qin Ping Zhu Chen-Xi Ouyang Xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties