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High-resolution short time interval measurement system implemented in a single FPGA chip

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Chinese Science Bulletin 2011年第12期56卷 1285-1290页

作者： wang hai ZHANG min LIU Jie Department of Measurement and Control Xidian University Xi' an 710071 China

This study proposes a high-resolution short time interval measurement system based on the Vernier delay line (VDL) method. It should be noted that the programmable delay elements (PDEs) in the Xilinx field programmable gate arrays (FPGAs) provide a novel realization of delay lines. The delay lines can provide an accurate delay difference of 50 ps, which is process, voltage and temperature (PVT) invariant. An excellent consistency for the delay lines can be achieved by adjusting the timing and layout to minimize the measurement errors. The resolution achieved was 58 ps. Experimental results indicate a measurement standard deviation of 36 ps, a differential nonlinearity (DNL) of 36 ps and integral nonlinearity (INL) of 14 ps. The system features high accuracy, easy implementation and low cost.

关键词： FPGA芯片测量系统时间间隔高分辨率现场可编程门阵列 Xilinx 延迟线积分非线性

VIBRATION OF A SINGLE PROTEIN BUBBLE IN BINGHAM LIQUID

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Journal of Hydrodynamics 2009年第5期21卷 658-668页

作者： wang hai-min JIANG Xu-ping MA Jian-min ZHANG Wen College of Power Engineering University of Shanghai for Science and Technology Shanghai 200093 China Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China

The vibration of a single protein bubble may take place under the action of high pressure difference. In this process, the bubble wall may experience a finite deformation. The equation describing the dynamics of the protein bubble with viscoelastic film in Bingham liquid is derived. A numerical solution to this equation is carried out to study the effect of liquid pressure, the characteristic parameters of Bingham liquid and the viscosity of the protein film on the finite deformation of the bubble. The results show that the vibration of the protein bubble wall is caused by the action of pressure difference, the elastic stress in finite deformation and the dissipation of viscosity of the protein film and Bingham liquid. The vibration is nonlinear. Decreasing the pressure difference between gas and Bingham liquid on both sides of the protein bubble will lead to a change of vibration performance. The frequency and amplitude are reduced, tegether with the speed of vibration damping. In addition, the deformation rate of the bubble is smaller when the amplitude of vibration is reduced, which means shorter time to reach a balance state. On the other side, the increase of the magnitude of viscosity of the protein film or the plastic viscosity of Bingham liquid can restrain the vibration of the protein bubble wall in the course of finite deformation, as a result, the load bearing capacity of bubble is enhanced.

关键词： protein bubble Bingham liquid vibration finite deformation viscosity

Synergistic effect of Co and Co_(6)Mo_(6)C for electroreduction of nitrate to ammonia on Co-MOF derived Co_(6)Mo_(6)C/Co/NC

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Nano Research 2024年第7期17卷 5807-5816页

作者： Xinyan wang Yue Cao Yan hai Xiaoman Li min Luo State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering School of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China

Electrocatalytic nitrate reduction reaction(e-NO_(3)RR)offers a promising alternative method for nitrogen cycling and ammonia(NH3)production under ambient ***,the method is still in the dilemma of lowering the reaction overpotential and increasing the reaction *** successfully developed the composition-adjustable Co_(6)Mo_(6)C/Co/N-doped carbon(NC)catalysts by in situ carbonization of Co-based metal-organic framework(MOF)with the constrained phosphomolybdic *** adjusting the ratio of Co0 and Co_(6)Mo_(6)C,Co_(6)Mo_(6)C/Co/NC-3 could satisfy both NO_(3)−conversion at low potential and NH_(x)hydrogenation,and synthesize ammonia efficiently through the synergistic effect of Co0 and Co_(6)Mo_(6)*** achieved an ammonia yield rate as 1233.2μg·h^(−1)·mgcat^(−1)and Faradaic efficiency of NH4+93.6%at−0.33 V *** hydrogen electrode(RHE).Importantly,density functional theory(DFT)calculations and experimental results have demonstrated for the first time the excellent adsorption of nitrite(NO_(2)^(−))by the Mo sites of Co_(6)Mo_(6)C during e-NO_(3)RR,avoiding the undesirable accumulation of NO_(2)^(−).

关键词： synergistic effect nitrate electroreduction Co_(6)Mo_(6)C ammonia synthesis

Prevotella and succinate treatments altered gut microbiota,increased laying performance,and suppressed hepatic lipid accumulation in laying hens

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Journal of Animal Science and Biotechnology 2024年第2期15卷 844-861页

作者： min Liu Zeyue Kang Xikang Cao Hongchao Jiao Xiaojuan wang Jingpeng Zhao hai Lin College of Animal Science and Technology Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and PreventionKey Laboratory of Efficient Utilization of Non‑Grain Feed Resources(Co‑Construction by Ministry and Province)Ministry of Agriculture and Rural AffairsShandong Agricultural UniversityTai’an 271018China

Background This work aimed to investigate the potential benefits of administering Prevotella and its primary metabolite succinate on performance,hepatic lipid accumulation and gut microbiota in laying *** One hundred and fifty 58-week-old Hyline Brown laying hens,with laying rate below 80%and plasma triglyceride(TG)exceeding 5 mmol/L,were used in this *** hens were randomly allocated into 5 groups and subjected to one of the following treatments:fed with a basal diet(negative control,NC),oral gavage of 3 mL/hen saline every other day(positive control,PC),gavage of 3 mL/hen Prevotella melaninogenica(10^(7)CFU/mL,PM)or 3 mL/hen Prevotella copri(10^(7)CFU/mL,***)every other day,and basal diet supplemented with 0.25%sodium succinate(Succinate).The results showed that PM and *** treatments significantly improved laying rate compared to the PC(P0.05).PM treatment increased(P<0.05)the mRNA levels of genes PGC-1βand APB-5B at week 4,and ACC and CPT-1 at week *** results indicated enhanced antioxidant activities at week 8,as evidenced by reduced hepatic malondialdehyde(MDA)level and improved antioxidant enzymes activities in PM and Succinate groups(P<0.05).Supplementing with Prevotella or succinate can alter the cecal ***,the abundance of Prevotella in the Succinate group was significantly higher than that in the other 4 groups at the family and genus levels(P<0.05).Conclusions Oral intake of Prevotella and dietary supplementation of succinate can ameliorate lipid metabolism of laying *** beneficial effect of Prevotella is consistent across different *** finding highlights that succinate,the primary metaboli

关键词： Fatty liver Gut microbiota Laying hen Prevotella Succinate

Clinical manifestations and spermatogenesis outcomes in Chinese patients with congenital hypogonadotropic hypogonadism caused by inherited or de novo FGFR1 mutations

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Asian Journal of Andrology 2024年第4期26卷 426-432页

作者： Yu-Fan Yang hai-Lu Ma Xi wang min Nie Jiang-Feng Mao Xue-Yan Wu Department of Endocrinology Peking Union Medical College HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100730China.

Fibroblast growth factor receptor 1(FGFR1)mutations are associated with congenital hypogonadotropic hypogonadism(CHH)through inheritance or spontaneous *** detected FGFR1 mutations in a Chinese cohort of 210 CHH patients at Peking Union Medical College Hospital(Beijing,China)using next-generation and Sanger *** assessed missense variant pathogenicity using six bioinformatics tools and compared clinical features and treatment outcomes between inherited and de novo mutation *** 19 patients with FGFR1 mutations,three were recurrent,and 16 were novel *** of the novel mutations were likely pathogenic according to the American College of Medical Genetics and Genomics(ACMG)guidelines,with the prevalent P366L *** majority of FGFR1 mutations was inherited(57.9%),with frameshift mutations exclusive to the de novo mutation *** inherited mutation group had a lower incidence of cryptorchidism,short stature,and skeletal *** the inherited mutation group,luteinizing hormone(LH)levels were 0.5 IU l−1,follicle-stimulating hormone(FSH)levels were 1.0 IU l−1,and testosterone levels were 1.3 nmol l−*** contrast,the de novo group had LH levels of 0.2 IU l−1,FSH levels of 0.5 IU l−1,and testosterone levels of 0.9 nmol l−1,indicating milder hypothalamus–pituitary–gonadal axis(HPGA)functional deficiency in the inherited *** inherited mutation group showed a tendency toward higher spermatogenesis *** conclusion,this study underscores the predominance of inherited FGFR1 mutations and their association with milder HPGA dysfunction compared to de novo mutations,contributing to our understanding of the genetic and clinical aspects of FGFR1 mutations.

关键词： congenital hypogonadotropic hypogonadism de novo FGFR1 inherited

A Study on the Impact of Chemical Structure on the Evolution of Aggregate Structure in Fiber-shaped High Density Polyethylene Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1557-1565,I0013页

作者： Bing wang Yuan-Chu Gao hai wang Hui Niu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing *** chemical structure characterization,morphology observation,thermal and mechanical properties investigation,as well as aggregate structure analysis,this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing.A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing,resulting in a lower orientation of the PE ***,lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain *** uneven morphology of fibershaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding,which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate *** Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shap

关键词： High density polyethylene vitrimer Fiber-shaped Aggregate structures Transesterification reaction

Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review

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China Geology 2024年第3期7卷 533-550页

作者： Shi-min Zhen Da-zhao wang Zhong-jian Zha hai-jun Bai Jiang wang Development and Research Center of China Geological Survey Ministry of Natural ResourcesBeijing 100037China Technical Guidance Center for mineral Resources Exploration Ministry of Natural ResourcesBeijing 100037China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Institute of Geological Surveying and Mapping Technology of Anhui Province Hefei 230022China Third Geological Brigade of Hebei Bureau of Geology and mineral Resources Zhangjiakou 075000China Ulanqab Real Estate Registration Center Ulanqab 012099China

The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of *** paper presents a new understanding for Dongping ore system,based on the previous *** mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the *** compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou ***-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage *** systematic changes are closely related to the processes of mineral precipitation and fluid *** precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur *** of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native *** on these hypotheses,this paper present a polyphase metallogenic model as *** the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early *** the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.

关键词： mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton mineral exploration engineering

Effect of V on high-temperature mechanical properties of Al-5Cu-1.5Ni alloy

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Journal of Iron and Steel Research International 2024年第7期31卷 1792-1810页

作者： Jun-ge Cui Yong-bin Chen Xiang-zhou Fu hai-long Yang Han-zhang wang An-min Li Li-wen Pan School of Resources Environment and MaterialsGuangxi UniversityNanning 530004GuangxiChina State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Nanning 530004GuangxiChina Guangxi Higher Education Key Laboratory of Advanced Materials Nanning 530004GuangxiChina

The effects of V on microstructure,room temperature,and high-temperature(350℃)mechanical properties of Al-5Cu-1.5Ni alloy were *** results show that Al-5Cu-1.5Ni-xV alloys mainly compriseα-Al,Al_(2)Cu,Al_(3)(Ni,Cu)_(2),Al_(3)Ni,Al7Cu4Ni,and Al_(10)V *** addition of V can signally refineα-Al dendritic structure,which improves the mechanical properties of the as-cast alloys at room and high *** T6 heat treatment(540℃/12 h/WC+170℃/8 h/AC),α-Al,network skeleton structure Al_(3)(Ni,Cu)_(2),and Al_(10)V phases all show coarsening,while the fine nano-θ'-Al_(2)Cu precipitated from the matrix and dispersed *** introduction of V promotes the quantity of precipitatedθ'-Al_(2)Cu *** ultimate tensile strength of the heat-treated alloys at room and high temperatures is greatly improved compared to that of the as-cast *** highest high-temperature ultimate tensile strength of the alloys with V is 111.8 MPa,21.5%higher than that of the base *** analysis shows that the improvement of high-temperature mechanical properties after heat treatment is mainly due to the introduction of V,increasing the precipitated quantity of nano-θ'-Al_(2)Cu particles and improving its thermal *** dispersion strengthening effect ofθ'-Al_(2)Cu particles exceeds the weakening effect of other adverse microstructures on the mechanical properties.

关键词： Al-Cu-Ni-V alloy θ'-Al_(2)Cu phase Heat treatment Microstructure Mechanical property

Derivation of Expanded Isospectral-Nonisospectral Integrable Hierarchies via the Column-vector Loop Algebra

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 778-800页

作者： hai-feng wang Yu-feng ZHANG School of Science Jimei UniversityXiamen 361021China School of Mathematics China University of Mining and TechnologyXuzhou 221116China

A scheme for generating nonisospectral integrable hierarchies is *** on the method,we deduce a nonisospectral hierarchy of soliton equations by considering a linear spectral *** follows that the corresponding expanded isospectral and nonisospectral integrable hierarchies are deduced based on a 6 dimensional complex linear space ■.By reducing these integrable hierarchies,we obtain the expanded isospectral and nonisospectral derivative nonlinear Schr?dinger *** using the trace identity,the biHamiltonian structure of these two hierarchies are also ***,some symmetries and conserved quantities of the resulting hierarchy are discussed.

关键词： expanded isospectral-nonisospectral integrable hierarchies column-vector loop algebra bi-Hamiltonian structure symmetry