检索结果-南通市图书馆

Orientational growth behavior and mechanism of delta(δ)phase precipitation in cold-rolled Inconel 718 alloy during heat treatment

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第1期31卷 264-274页

作者： Neng-yong ye Guang-liang zhang Tian-yue Huang ming Cheng Shi-hong zhang Lei wang School of Materials Science&Engineering Taizhou UniversityTaizhou318000ZhejiangChina Institute of Metal Research Chinese Academy of SciencesShenyang110016LiaoningChina

Due to the important role ofδphase's quantity and morphology in the mechanical and fatigue properties of Inconel 718 alloy and its components,it is necessary to renew insights into the effect of cold deformation on theδphase precipitation,especially on the morphology ***,the nucleation and growth behavior ofδphase in cold-rolled Inconel 718 alloy during aging were *** results show that the precipitation rate and volume fraction ofδphase increase with increasing the cold rolling reduction from 10%to 50%.The volume fraction ofδphase reaches equilibrium after 5 h,remaining at 5.98%,6.52%,and 6.79%under different rolling reductions(10%,30%,and 50%),*** nucleation ofδphase mainly occurs on different sites(grain boundaries,new twin boundaries and old twin boundaries)under 10%rolling reduction,whileδphase mainly nucleates on the new grain boundaries of static recrystallization due to 50%rolling *** the growth ofδphase undergoes a process of alternate orientation growth from spherical(nucleation)→short rod(longitudinal orientation growth)→short rod(radial orientation growth)→dynamic *** 10%rolling reduction,δphase tends to grow into the matrix,while under 50%rolling reduction,the orientation grows faster and is easily affected by the grain boundary curvature.

关键词： Inconel 718 alloy Cold rolling δphase Orientation growth Morphology evolution

Semi-supervised remote sensing image scene classification with prototype-based consistency

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第2期37卷 459-470页

作者： Yang LI zhang LI zi wang Kun wang Qifeng YU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Deep learning significantly improves the accuracy of remote sensing image scene classification,benefiting from the large-scale ***,annotating the remote sensing images is time-consuming and even tough for *** neural networks trained using a few labeled samples usually generalize less to new unseen *** this paper,we propose a semi-supervised approach for remote sensing image scene classification based on the prototype-based consistency,by exploring massive unlabeled *** this end,we,first,propose a feature enhancement module to extract discriminative *** is achieved by focusing the model on the foreground ***,the prototype-based classifier is introduced to the framework,which is used to acquire consistent feature *** conduct a series of experiments on NWPU-RESISC45 and Aerial Image Dataset(AID).Our method improves the State-Of-The-Art(SOTA)method on NWPU-RESISC45 from 92.03%to 93.08%and on AID from 94.25%to 95.24%in terms of accuracy.

关键词： Semi-supervised learning Remote sensing Scene classification Prototype network Deep learning

Run-and-Tumble Dynamics and Mechanotaxis Discovered in Microglial Migration

在线全文

学校读者我要写书评

暂无评论

Research 2024年第2期2023卷 95-103页

作者： Yiyu zhang Da Wei Xiaochen wang Boyi wang ming Li Haiping Fang Yi Peng Qihui Fan Fangfu ye Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Wenzhou Institute University of Chinese Academy of SciencesWenzhouZhejang 325000China Songshan Lake Materials Laboratory DongguanGuangdong 523808China School of Science East China University of Science and TechnologyShanghai 200237China Oujang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)WenzhouZhejiang 325000China

Microglia are resident macrophage cells in the central nervous system that search for pathogens or abnormal neural activities and migrate to resolve the *** effective search and targeted motion of macrophages mean dearly to maintaining a healthy brain,yet little is known about their migration *** this work,we study microglial motion with and without the presence of external *** discover that the cells are promptly attracted by the applied forces(i.e.,mechanotaxis),which is a tactic behavior as yet unconfirmed in ***,in both the explorative and the targeted migration,microglia display dynamics that is strikingly analogous to bacterial run-and-tumble motion.A closer examination reveals that microglial run-and-tumble is more sophisticated,e.g.,they display a short-term memory when tumbling and rely on active steering during runs to achieve mechanotaxis,probably via the responses of mechanosensitive ion *** differences reflect the sharp contrast between microglia and bacteria cells(eukaryotes ***)and their environments(compact tissue ***).Further analyses suggest that the reported migration dynamics has an optimal search efficiency and is shared among a subset of immune cells(human monocyte and macrophage).This work reveals a fruitful analogy between the locomotion of 2 remote systems and provides a framework for studying immune cells exploring complex environments.

关键词： analogy closer prompt

Integrating machine learning and CALPHAD method for exploring low-modulus near-β-Ti alloys

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第1期43卷 309-323页

作者： Hao Zou Yue-Yan Tian Li-Gang zhang Ren-Hao Xue zi-Xuan Deng ming-ming Lu Jian-Xin wang Li-Bin Liu School of Computer Science and Engineering Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Traditional theoretical and empirical calculation methods can guide the design of β-and metastable β-alloys for bio-titanium. However, it is still difficult to obtain novel near-β-Ti alloys with low modulus. This study developed a method that combines machine learning with calculation of phase diagrams(CALPHAD) to facilitate the design of near-β-Ti alloys. An elastic modulus database of Ti–Nb–Zr–Mo–Ta–Sn system was constructed first, and then three features(the electron to atom ratio, mean absolute deviation of atom mass, and mean electronegativity) were selected as the key factors of modulus by performing a three-step feature selection. With these features, a highly accurate model was built for predicting the modulus of near-β-Ti alloys. To further ensure the accuracy of modulus prediction, machine learning with the elastic constants calculated was leveraged by CALPHAD database. The root mean square error of the well-trained model can be as low as 6.75 GPa. Guided by the prediction of machine learning and CALPHAD, three novel near-β-Ti alloys with elastic modulus below 50 GPa were successfully designed in this study. The best candidate alloy(Ti–26Nb–4Zr–4Sn–1Mo–Ta) exhibits an ultra-low modulus(36.6 GPa) after cold rolling with a thickness reduction of 20%. Our method can greatly save time and resources in the development of novel Ti alloys, and experimental verifications have demonstrated the reliability of this method.

关键词： Near-β-Ti alloy Machine learning Calculation of phase diagram Low-modulus alloy Feature selection

Enhanced Crystallization of Poly(butylene adipate-co-terephthalate)by a Self-assembly Nucleating Agent

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第5期42卷 663-674,I0010页

作者： Cheng Zhou Kun Chen zi-Heng zhang Meng-Fan Jing Chun-Tai Liu Chang-Yu Shen Ya-ming wang State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou450002China

Poly(butylene adipate-co-terephthalate)(PBAT)is a promising biodegradable flexible polymer but suffers from slow crystallization rate,making it less attractive for some applications like the injection-molded products in comparison with low-density polyethylene(LDPE).This work aimed to accelerate the crystallization of PBAT by adding a self-assembly nucleating agent octamethylenedicarboxylic dibenzoylhydrazide(OMBH).PBAT/OMBH composites with various OMBH contents(0 wt%,0.5 wt%,0.7 wt%,1 wt%,2 wt%,3 wt%and 5 wt%)were prepared through *** effect of OMBH on the crystallization behavior,morphologies and mechanical properties of PBAT was *** highest nucleation efficiency value of 59.6%was achieved for PBAT with 0.7 wt%OMBH,much higher than that of 22.7%for PBAT with 0.7 wt%*** force microscopy results showed that OMBH formed fine fibers and induced the formation of transcrystalline layers of *** transform infrared spectroscopy(FTIR)combined with two-dimensional correlation spectra suggested that the intermolecular dipole-dipole N—H…O=C interactions but not hydrogen bond between OMBH and PBAT promoted the crystallization of PBAT in the initial period of *** presence of OMBH did not change the crystal form of PBAT but had positive contribution in enhancing its crystallinity and mechanical *** work is essential for preparing PBAT with high crystallization rate,enhancing its potential applications in injection-molded products.

关键词： Poly(butylene adipate-co-terephthalate) Biodegradable Self-assembly nucleating agent Crystallization

Pairs of thiol-substituted 1,2,4-triazole-based isomeric covalent inhibitors with tunable reactivity and selectivity

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第7期35卷 329-335页

作者： Shiqi Xu zi ye Shuang Shang Fengge wang Huan zhang Lianguo Chen Hao Lin Chen Chen Fang Hua Chong-Jing zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of Active Substance Discovery and Druggability EvaluationInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study(BZ0150)Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China The First Affiliated Hospital of Wenzhou Medical University Wenzhou 325000China

Covalent bioactive compounds are successfully used in clinic and attracted intense research efforts in the fundamental study as well as drug *** advantageous effects of covalent compounds compared with non-covalent ones are highly dependent on electrophilic ***,electrophilic warheads with tunable reactivity and selectivity are highly demanded in fields of medicinal chemistry and chemical ***,we report a novel electrophilic warhead,chloromethyl group activated by thiol-substituted 1,2,***,a pair of regioisomers could be simultaneously occurred in the step of alkylation during the synthesis of this unique *** is a rare example that the alkylation could simultaneously generate these two separable regioisomers of 1,2,4-triazole at the nitrogen or sulfur *** covalent-working mechanism of this new warhead is confirmed by various chemoproteomics experiments including target identification and binding site ***,the reactivity and selectivity of this new electrophilic warhead could be efficiently tuned by virtue of stereo ***,one pair of regioisomers(19S and 19X)induced distinct modes of cell *** 19S could induce apoptosis of colon cancer cells while 19X could induce both apoptosis and ***,this study provides pairs of novel electrophilic warheads that could be useful not only in supporting the design of covalent compounds for drug discovery but also in providing chemical probes for the fundamental biological study.

关键词： Electrophilic warhead Covalent inhibitor 1,2,4-Triazole Chemical proteomics GSTO1

Enhanced photoelectrochemical water splitting with a donor-acceptor polyimide

在线全文

学校读者我要写书评

暂无评论

Frontiers in Energy 2024年第4期18卷 463-473页

作者： Hongyu QU Xiaoyu XU Longfei HONG Xintie wang Yifei zan Huiyan zhang Xiao zhang Sheng CHU Key Laboratory of Energy Thermal Conversion and Control of the Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China

Polyimide(PI)has emerged as a promising organic photocatalyst owing to its distinct advantages of high visible-light response,facile synthesis,molecularly tunable donor-acceptor structure,and excellent physicochemical ***,the synthesis of high-quality PI photoelectrode remains a challenge,and photoelectrochemical(PEC)water splitting for PI has been less ***,the synthesis of uniform PI photoelectrode films via a simple spin-coating method was reported,and their PEC properties were investigated using melamine as donor and various anhydrides as *** influence of the conjugate size of aromatic unit(phenyl,biphenyl,naphthalene,perylene)of electron acceptor on PEC performance were studied,where naphthalene-based PI photoelectrode exhibited the highest photocurrent *** is resulted from the unification of widerange light absorption,efficient charge separation and transport,and strong photooxidation *** paper expands the material library of polymer films for PEC applications and contributes to the rational design of efficient polymer photoelectrodes.

关键词： polyimide(PI)film photoelectrochemistry band structure engineering aromatic unit

Topologically protected entanglement switching around exceptional points

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第8期13卷 1631-1644页

作者： zan Tang Tian Chen Xing Tang Xiangdong zhang Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology100081 BeijingChina

The robust operation of quantum entanglement states is crucial for applications in quantum information,computing,and communications^(1–3).However,it has always been a great challenge to complete such a task because of decoherence and ***,we propose theoretically and demonstrate experimentally an effective scheme to realize robust operation of quantum entanglement states by designing quadruple degeneracy exceptional *** encircling the exceptional points on two overlapping Riemann energy surfaces,we have realized a chiral switch for entangled states with high *** to the topological protection conferred by the Riemann surface structure,this switching of chirality exhibits strong robustness against perturbations in the encircling ***,we have experimentally validated such a scheme on a quantum walk *** work opens up a new way for the application of non-Hermitian physics in the field of quantum information.

关键词： exceptional quantum Riemann

A Local Tb Theorem for Square Functions and Parabolic Layer Potentials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第8期40卷 1941-1966页

作者： Zhi Dan wang Guo ming zhang School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816P.R.China Frontiers Science Center for Nonlinear Expectations Ministry of EductionResearch Center for Mathematics and Interdisciplinary SciencesShandong UniversityQingdao266237P.R.China

In this paper,we give a locally parabolic version of Tb theorem for a class of vector-valued operators with off-diagonal decay in L^(2) and certain quasi-orthogonality on a subspace of L^(2),in which the testing functions themselves are also *** an application,we establish the boundedness of layer potentials related to parabolic operators in divergence form,defined in the upper half-space Rn+2+:={(x,t,λ)∈R^(n+1)×(0,∞)},with uniformly complex elliptic,L^(∞),t,λ-independent coefficients,and satisfying the De Giorgi/Nash estimates.

关键词： Local Tb theorems Calderon-Littlewood-Paley family Parabolic layer potentials Carleson measure estimates