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Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-lin Shen jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Recent progress in self-propelled particles

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Journal of Hydrodynamics 2024年第1期36卷 61-77页

作者： Zhen-yu Ouyang jian-zhong lin Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315201China Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou310027China

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria,fungi,and algae in nature,and researchers have taken a long interest in exploring their swimming mechanisms for more than a *** in the past 20 years,with the development of computational fluid dynamics and flow display technology,as well as the need for the design of synthetic self-propelled particles and micro-swimming devices,self-propelled particles have become the forefront and hotspot of current research in the field of fluid *** paper first introduces the swimming characteristics of common self-propelled particles,leading to a classic“squirmer”type self-propelled particle *** this basis,a systematic introduction and summary of the theoretical and numerical simulation research of“squirmer”will be ***,the main challenges and opportunities faced by the current research will be summarized.

关键词： Self-propelled particles multiphase flow hydrodynamic interaction

Multiple generation effects of high temperature on the development and fecundity of Bemisia tabaci （Gennadius）（Hemiptera Aleyrodidae） biotype B

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Insect Science 2013年第4期20卷 541-549页

作者： jian-ying Guo lin Cong Fang-Hao Wan State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of AgriculturalSciences Beijing China

Insects are ectotherms and their ability to resist temperature stress is limited. The immediate effects of sub-lethal heat stress on insects are well documented, but longer- term effects of such stresses are rarely reported. In this study, survival, development and reproduction of the whitefly, Bemisia tabaci （Gennadius）（Hemiptera： Aleyrodidae） biotype B, were compared over five consecutive generations at 27, 31 and 35℃ and for one generation at 37 ℃. Both temperature and generation significantly affected the fitness of the whitefly. These impacts were more dramatic with increasing generations and temperatures. Among the experimental temperatures, the most favorable for development and reproduction were 27 ℃ and 31 ℃. At 27 ℃, survival, development and fecundity were all stable over these five generations. At 31 ℃, immature survival rate was the highest in the fifth generation, but female fecundities decreased in the fourth and fifth generations. At 35 ℃, egg hatching rate, immature survival rate and female fecundity decreased significantly in the fourth and fifth generations. At 37 ℃, survival ofB. tabaci was not adversely affected, but female fecundity at 37 ℃ was less than 10% of that at 27 ℃ or 31 ℃. These results demonstrate that the lethal high temperature for B. tabaci is over 37 ℃, and the whitefly population continued expanding in the five generations at 35 ℃. The ability orB. tabaci biotype B to survive high temperature stress will play an important role in its population extension under global warming.

关键词： Bemisia tabaci biotype B high temperature stress multiple generation ef-fects population expansion

Tuning Surface Molecular Design of Porous Carbon for Blue Energy Harvesting

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Research 2024年第1期2023卷 651-662页

作者： jian Yu Zhong-lin Wang Tianwei Ma Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life ***,because of limited performance,existing systems do not lend themselves to practical *** it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive ***,we show that manipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the *** findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how manipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

Modification of a magnetic carbon composite for ciprofloxacin adsorption

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Journal of Environmental Sciences 2016年第11期28卷 179-188页

作者： Haixin Mao Shikui Wang jian-ying lin Zengshuang Wang Jun Ren College of Chemistry and Chemical Engineering Key Laboratory of Coal Science and Technology Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

A magnetic carbon composite, Fe3O4/C composite, was fabricated by one-step hydrothermal synthesis, modified by heat treatment under an inert atmosphere（N2）, and then used as an adsorbent for ciprofloxacin（CIP） removal. Conditions for the modification were optimized according to the rate of CIP removal. The adsorbent was characterized by Fourier transform infrared spectroscopy, X-ray diffraction measurements, vibrating-sample magnetometry,scanning electron microscopy, transmission electron microscopy, and N2adsorption/desorption isotherm measurements. The results indicate that the modified adsorbent has substantial magnetism and has a large specific area, which favor CIP adsorption. The effects of solution p H, adsorbent dose, contact time, initial CIP concentration, ion strength, humic acid and solution temperature on CIP removal were also studied. Our results show that all of the above factors influence CIP removal. The Langmuir adsorption isotherm fits the adsorption process well, with the pseudo second-order model describing the adsorption kinetics accurately. The thermodynamic parameters indicate that adsorption is mainly physical adsorption. Recycling experiments revealed that the behavior of adsorbent is maintained after recycling for five times. Overall, the modified magnetic carbon composite is an efficient adsorbent for wastewater treatment.

关键词： Magnetic carbon composite Modification Ciprofloxacin Adsorption

Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

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Journal of Iron and Steel Research(International) 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian Miao Jia-xin lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Emerging role of lncRNAs as mechanical signaling molecules in mechanotransduction and their association with Hippo-YAP signaling:a review

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 280-292页

作者： Siyi lin Xinyu HE ying WANG Yu CHEN Aifu lin College of Medicine Zhejiang UniversityHangzhou 310058China College of Life Sciences Zhejiang UniversityHangzhou 310058China Cancer Center Zhejiang UniversityHangzhou 310058China Key Laboratory for Cell and Gene Engineering of Zhejiang Province Hangzhou 310058China International School of Medicine International Institutes of Medicinethe Fourth Affiliated Hospital of Zhejiang University School of MedicineYiwu 322000China Key Laboratory of Cancer Prevention and Intervention China National Ministry of EducationHangzhou 310058China Future Health Laboratory Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China

Cells within tissues are subject to various mechanical forces,including hydrostatic pressure,shear stress,compression,and *** mechanical stimuli can be converted into biochemical signals through mechanoreceptors or cytoskeleton-dependent response processes,shaping the microenvironment and maintaining cellular physiological *** studies have demonstrated the roles of Yes-associated protein(YAP)and its homolog transcriptional coactivator with PDZ-binding motif(TAZ)as mechanotransducers,exerting dynamic influence on cellular phenotypes including differentiation and disease *** regulatory function entails the involvement of the cytoskeleton,nucleoskeleton,integrin,focal adhesions(FAs),and the integration of multiple signaling pathways,including extracellular signal-regulated kinase(ERK),wingless/integrated(WNT),and Hippo ***,emerging evidence substantiates the implication of long non-coding RNAs(lncRNAs)as mechanosensitive molecules in cellular *** this review,we discuss the mechanisms through which YAP/TAZ and lncRNAs serve as effectors in responding to mechanical ***,we summarize and elaborate on the crucial signal molecules involved in mechanotransduction.

关键词： YAP/TAZ Long non-coding RNA(lncRNA) Mechanotransduction F-actin

Neuronomodulation of Excitable Neurons

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Neuroscience Bulletin 2024年第1期40卷 103-112页

作者： Yizhang Chen lin Xiao jian Qiu Institute of Neuroscience Second Military Medical UniversityShanghai 200433China Institute for Brain Research and Rehabilitation Key Laboratory of BrainCognition and Education Sciences of Ministry of EducationSouth China Normal UniversityGuangzhou 510631China Department of Chemical Physiology and Biochemistry Oregon Health and Science UniversityPortlandOR 97239USA

Neuronomodulation refers to the modulation of neural conduction and synaptic transmission(i.e.,the conduction process involved in synaptic transmission)of excitable neurons via changes in the membrane potential in response to chemical substances,from spillover neuro-transmitters to paracrine or endocrine hormones circulating in the *** can be direct or indirect,depending on the transduction pathways from the ligand binding site to the ion pore,either on the same molecule,*** ion channel,or through an intermediate step on different *** major players in direct neurono-modulation are ligand-gated or voltage-gated ion *** key process of direct neuronomodulation is the binding and chemoactivation of ligand-gated or voltage-gated ion channels,either orthosterically or allosterically,by various *** neuronomodulation involves metabotropic receptor-mediated slow potentials,where steroid hormones,cytokines,and chemokines can implement these *** neuronomodulation is of great significance for understanding the physiological mechanisms of brain function,and the occurrence and treatment of diseases.

关键词： Neuron Membrane potential Excitability Chemoactivation Neuronomodulation

Turbulent Image Restoration in Atmosphere with Cyclopean Processing via Binocular Fusion

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Chinese Physics Letters 2024年第8期41卷 33-38页

作者： Han Yao Jin-Yan lin Li-Bang Chen Yi-Kun Liu jian-ying Zhou State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-Sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing School of Physics and AstronomySun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China

The outstanding issue to overcoming atmospheric turbulence on distant imaging is a fundamental interest and technological *** propose a novel scenario and technique to restore the optical image in turbulent environmental by referring to Cyclopean image with binocular *** human visual intelligence,image distortion resulting from the turbulence is shown to be substantially *** simulation results taking into account of the atmospheric turbulence,optical image system,image sensors,display and binocular vision perception are presented to demonstrate the robustness of the image restoration,which is compared with a single channel planar optical imaging and *** involving binocular telescope,image recording and the stereo-image display is conducted and good agreement is obtained between the simulation with perceptive experience.A natural extension of the scenario is to enhance the capability of anti-vibration or anti-shaking for general optical imaging with Cyclopean image.

关键词： image turbulence shaking