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The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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Science china(Technological Sciences) 2006年第2期49卷 238-247页

作者： zhang hai’ou1, qian yingping1,3. WANG Guilan1 & ZHENG Qiguang2.1. School of Material Science and Technology, Huazhong University of Science and Technology,{2.,{3. 2. Institute of Laser Technology and Engineering, Huazhong University of Science and Technology,{2.,{3. 3. Mechanical Engineering College, Hubei University of Technology, wuhan 43.068,{3. School of Material Science and Technology Huazhong University of Science and Technology Wuhan China Mechanical Engineering College Hubei University of Technology Wuhan China Institute of Laser Technology and Engineering Huazhong University of Science and Technology Wuhan China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Continuous-flow enzymatic synthesis of chiral lactones in a three-dimensional microfluidic reactor

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Chinese Chemical Letters 2024年第3期35卷 299-303页

作者： Xuelei Deng Meng Fan Miao Wu Xiaoyan zhang Ya Cheng Jianye Xia yingping Zhuang Weiping Zhu Xuhong {2. Yunpeng Bai State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Center for BiomanufacturingEast China University of Science and TechnologyShanghai 200237China The Extreme Optoelectromechanics Laboratory School of Physics and Materials ScienceEast China Normal UniversityShanghai 200241China Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China

A new continuous-flow process for the enzymatic synthesis of optically pureγ-lactones,which are used as flavors and fragrances in the food and cosmetic industries,was developed in a three-dimensional microfluidic *** microchannels(175 mm in length,0.9 mm in depth,and 1.72.mL in volume)were carved precisely inside a single borosilicate glass(90 mm×75 mm×12.mm)with ultrafast femtosecond laser *** flow field analysis and reaction simulation showed that the mixing of substrates and enzymes was enhanced,allowing the adjustment of residence time in a wide ***_(V4),a carbonyl reductase with excellent catalytic activity and enantioselectivity towardγ/δ-keto acids,was employed for the asymmetric synthesis of various chiral lactones.3. mmol/L(R)-γ-decalactone(3.)can be obtained in 2. s with a space-time yield(STY)up to 16,877 g L^(-1)d^(-1),which is 14.4 times higher than the highest STY of batch reaction reported *** continuous-flow process was applied to the synthesis of 6 chiral *** addition,the scaled-up synthesis of 3. was carried out in 6 cascade microreactors continuously for 6 h,demonstrating the feasibility and stability of the 3. continuous-flow process in enzymatic synthesis of optically pure compounds.

关键词： Continuous-flow Flow chemistry Microreactor Biocatalysis Carbonyl reductase Asymmetric reduction

Investigation on the vortical structures by the Liutex method in turbulent channels at Re_(τ)=180 with scalloped and triangular riblet control

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Journal of Hydrodynamics 2024年第1期36卷 35-52页

作者： zhang-dan Yu Shang Jiang hai-dong Yu Bi-yu Pang Xin Dong Yi-{2. Wang School of Mathematical Sciences Soochow UniversitySuzhou215006China Beijing Institute of Astronautical System Engineering Beijing100076China

Riblets are a series of small protrusions formed along the flow direction,which have been extensively studied as a passive turbulent drag reduction *** and numerical simulations have shown that well-designed riblets can significantly reduce drag in turbulent flows,making them highly promising and valuable for various *** this study,we focus on a scalloped riblet,which is designed by smoothly connecting two third-order polynomials,and thus the sharpness of the tip and the curvature of the valley can be well *** conduct direct numerical simulations of turbulent channel with smooth plate,scalloped riblet-mounted and triangular riblet-mounted *** in wall units of W^(+)={3. and height-width ratio ofγ=0.5 are selected for both riblet *** with the smooth plate case,the scalloped riblet case achieves an 8.68%drag reduction,while the triangular riblet case achieves a 4.79%drag *** obtained drag reduction rate of the triangular riblet is consistent with previous experiments and simulations,and the results indicate that the scalloped riblet is more effective in reducing drag and deserves further *** compare turbulent statistics of the scalloped riblet case with those of the triangular riblet *** mean velocity profiles of riblets are similar,but both the Reynolds shear stress and second-order statistics of velocity fluctuations and Liutex are significantly reduced in the scalloped riblets controlled turbulent channel,indicating that the scalloped riblet can more effectively suppress the spanwise and wall-normal turbulent intensity near the *** also compare the pre-multiplied spectra of streamwise velocity and streamwise Liutex component for the three cases to investigate the energy distribution and characteristics of Liutex *** Liutex vortex identification method is also utilized to analyze the instantaneous flow field,which provides insights into the flow field and could be bene

关键词： Liutex vector riblet drag reduction tip sharpness turbulent channel scalloped

Supermassive Primordial Black Holes for Nano-Hertz Gravitational Waves and High-redshift JWST Galaxies

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Research in Astronomy and Astrophysics 2024年第9期24卷 1-6页

作者： hai-Long Huang Yong Cai Jun-qian Jiang Jun {2. Yun-Song Piao School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institute for Astrophysics School of PhysicsZhengzhou UniversityZhengzhou 450001China International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of SciencesBeijing 100190China Taiji Laboratory for Gravitational Wave Universe(Beijing/Hangzhou) University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China

Recently,observational hints for supermassive black holes have been accumulating,prompting the question:Can primordial black holes(PBHs)be supermassive,particularly with masses M■10^(9)M_(⊙)?A supercritical bubble,containing an inflating baby universe,that nucleated during inflation can evolve into a PBH in our observable *** find that when the inflaton slowly transitions past a neighboring vacuum,the nucleation rate of supercritical bubbles inevitably peaks,leading to a mass distribution of multiverse PBHs with a peak mass up to M■10^(11)M_(⊙).Thus,our mechanism naturally provides a primordial origin for supermassive black holes.

关键词： (cosmology:)early universe (cosmology:)inflation (galaxies:)quasars:supermassive black holes

PDK1 promotes breast cancer progression by enhancing the stability and transcriptional activity of HIF-1α

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Genes & Diseases 2024年第4期11卷 353-367页

作者： Yu Wei Dian zhang He Shi Husun qian Hongling Chen qian Zeng Fangfang Jin Yan Ye Zuli {3. Minkang Guo Bianqin Guo Tingmei Chen Key Laboratory of Clinical Laboratory Diagnostics(Ministry of Education) College of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China

Pyruvate dehydrogenase kinase 1(PDK1)phosphorylates the pyruvate dehydroge-nase complex,which inhibits its *** pyruvate dehydrogenase complex inhibits the tricarboxylic acid cycle and the reprogramming of tumor cell metabolism to glycolysis,which plays an important role in tumor *** study aims to elucidate how PDK1 pro-motes breast cancer *** found that PDK1 was highly expressed in breast cancer tissues,and PDK1 knockdown reduced the proliferation,migration,and tumorigenicity of breast cancer cells and inhibited the HIF-1α(hypoxia-inducible factor 1α)*** investigation showed that PDK1 promoted the protein stability of HIF-1αby reducing the level of ubiquitination of HIF-1α.The HIF-1αprotein levels were dependent on PDK1 kinase ***,HIF-1αphosphorylation at serine 451 was detected in wild-type breast cancer cells but not in PDK1 knockout breast cancer *** phosphorylation of HIF-1αat Ser 451 stabilized its protein levels by inhibiting the interaction of HIF-1αwith von Hippel-Lindau and prolyl hydroxylase *** also found that PDK1 enhanced HIF-1αtranscriptional *** summary,PDK1 enhances HIF-1αprotein stability by phosphorylating HIF-1αat Ser451 and promotes HIF-1αtranscriptional activity by enhancing the binding of HIF-1αto ***1 and HIF-1αform a positive feedback loop to promote breast cancer progression.

关键词： Breast cancer HIF-1α PDK1 Protein phosphorylation Transcriptional activity

Bi-Frobenius Algebra Structures on Quantum Complete Intersections

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1481-1504页

作者： hai JIN Pu zhang School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240P.R.China

This paper is to look for bi-Frobenius algebra structures on quantum complete intersections over field *** find a class of comultiplications,such that if√−1∈k,then a quantum complete intersection becomes a bi-Frobenius algebra with comultiplication of this form if and only if all the parameters qij=±***,it is proved that if√−1∈k then a quantum exterior algebra in two variables admits a bi-Frobenius algebra structure if and only if the parameter q=±√*** if−1/∈k,then the exterior algebra with two variables admits no bi-Frobenius algebra *** prove that the quantum complete intersections admit a bialgebra structure if and only if it admits a Hopf algebra structure,if and only if it is commutative,the characteristic of k is a prime p,and every ai a power of *** also provides a large class of examples of bi-Frobenius algebras which are not bialgebras(and hence not Hopf algebras).In commutative case,other two comultiplications on complete intersection rings are given,such that they admit non-isomorphic bi-Frobenius algebra structures.

关键词： Bi-Frobenius algebras coalgebras bialgebras Hopf algebras quantum complete intersections quantum exterior algebras

A chromatographic method for pursuing potential GPCR ligands with the capacity to characterize their intrinsic activities of regulating downstream signaling pathway

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Chinese Chemical Letters 2024年第10期35卷 425-429页

作者： Ting Li Xinxin Zheng Lejing Qu Yuanyuan ou Sai Qiao Xue Zhao Yajun zhang Xinfeng Zhao {2. Li Key Laboratory of Resource Biology and Biotechnology in Western china Ministry of EducationCollege of Life SciencesNorthwest UniversityXi'an 710069China

GPCRs are dominant targets for approved drugs and the discovery of lead compound targeting them is still ***-based screening technique is a promising platform to uncover GPCR ***,the intrinsic activities of them are seldom simultaneously determined during the *** beta2.adrenoceptor(β2.R)as a probe,this work created a strategy for screening GPCR ligands with simultaneous characterization of their downstream G protein binding responses associated with *** strategy included(i)the design and expression of a protein miniature formed byβ2.R and G proteinα-subunit(Gαs)using circularly permuted HaloTag(cpHalo)as a flexible linker;(ii)immobilization of the miniature onto silica gel by a click dehalogenation reaction;(iii)systematic characterization of the immobilized miniature by fluorescent and chromatographic studies,and(iv)simulating of ligand-inducedβ2.R-Gαs signaling cascade by chromatographic assays using GTP as an *** immobilized miniature exhibited specificity toβ2.R and Gαs antibodies and *** specificity is stable at least within fifteen days with the variation less than 1%.The intrinsic activities ofβ2.R ligands were distinguished by the changes of GTP chromatographic behaviors on Gαs-cpHalo-β2.R *** strengthened the binding affinity and kinetics of GTP with Gαs,while antagonist did not give any effect on *** the intrinsic activity evaluation,we believe,it will improve the attributes of chromatographic methods for drug discovery efforts with minimizing false-positive results.

关键词： Intrinsic efficacy GPCR-G protein miniature Circularly permuted HaloTag High-performance receptor chromatography GTP binding Agonist/antagonist

Laser-rewritable room temperature phosphorescence based on in-situ polymerized tartaric acid

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Science china Chemistry 2024年第9期67卷 3029-3038页

作者： Tuo-Yu Zhou Tai-Wen Li hai-Fu {2. Rui-Lin Chai qian Zhao Penglin {2. Guang-Yue Li qian-Wen Wang Chang Li Yu Shu Zhi Fan Sheng-Hua Li College of Chemical Engineering and Materials Science College of SciencesTianjin University of Science&TechnologyTianjin 300457China College of Chemical Engineering North China University of Science and TechnologyTangshan 063210China Tianjin Key Laboratory of Multiplexed Identification for Port Hazardous Chemicals Tianjin University of Science&TechnologyTianjin 300457China

Organic room temperature phosphorescence(RTP)materials have potential applications in information technology and ***,the precise control of the afterglow in reversible manners remains challenging for organic ***,we report a kind of organic RTP material fabricated by simple heating mixtures of tartaric acid(TA)and aromatic acids,which can switch their phosphorescence by *** mixtures show tunable phosphorescence from indigo to orange with phosphorescence efficiency of up to 53.99% due to locking different organic luminogens by the TA-formed matrix through the noncovalent *** afterglow of those materials lasts a few seconds and disappears by water fumigation,which can be repeated in response to wet/heat *** drop-casting those materials on glass slides,a laser-repatternable phosphorescence is achieved by facile laser direct writing and quenched by water *** results open the opportunity for the design of smart stimuli-responsive phosphorescence materials from sustainable natural products.

关键词： room temperature phosphorescence tunable afterglows tartaric acid laser direct writing stimuli-response

Amorphous Sb/C composite with isotropic expansion property as an ultra-stable and high-rate anode for lithium-ion batteries

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Rare Metals 2024年第5期43卷 2039-2052页

作者： Ze-Zhou Yang Cheng-Yi zhang Yu-Qing ou Zhi-Kang Su Yan Zhao Heng-Jiang Cong Xin-Ping Ai Jiang-Feng {3. Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular SciencesWuhan UniversityWuhan430072China Institute of Technological Sciences Wuhan UniversityWuhan 430072China

Antimony(Sb)is an intriguing anode material for Li-ion batteries(LIBs)owing to its high theoretical capacity of 660 m Ah·g^(-1)and appropriate working potential of~0.8 V(***^(+)/Li).However,just like all alloying materials,the Sb anode suffers from huge volume expansion(2.0%)during repeated insertion/extraction of Li+ions,resulting in structural deterioration and rapid capacity *** this work,a novel amorphous Sb/C composite with atomically dispersed Sb particles in carbon matrix is prepared via a straightforward high-energy ball milling *** intimate intermixing of amorphous Sb with C provides homogeneous element distribution and isotropic volume expansion during cycling,resulting in persistent structural ***,the disordered structure of amorphous material shortens the diffusion distance of lithium ions/electrons,promoting fast reaction kinetics and rate *** from the aforementioned effects,the amorphous Sb/C exhibits a high reversible capacity of53..4 m Ah·g^(-1)at 0.1 A·g^(-1)and retains 2.1.0 m Ah·g^(-1)at an ultrahigh current rate of 10.0 A·g^(-1).Even after 1500deep cycles at 2.0 A·g^(-1),the amorphous Sb/C electrode still maintains 86.3.of its initial capacity,which outperforms all existing Sb-based anodes reported so *** analysis further reveals a greatly reduced volume variation of merely 3..6%for the amorphous Sb/C electrode,much lower than that of 2.3.1%for crystalline Sb *** study presents a new approach to stabilizing Sb-based alloy anodes and contributes to the construction of high-performance amorphous anode materials for LIBs,enabling advanced energy storage.

关键词： Amorphous Sb/C anode Homogeneous element distribution Isotropic volume expansion Ultra-long cycle stability High-rate capability Lithium-ion battery