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Double casing warhead with sandwiched charge:The axial distribution of fragments velocities

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Defence Technology（防务技术） 2024年第4期34卷 201-216页

作者： Ping Ye Yongxiang Dong Qitian Sun Peizhuo Shi wang yao Yongnan Li Yujing Li Mingze Li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity,and the previous work has presented a calculation formula to determine the maximum fragment velocity.The current work builds on the published formula to further develop a formula for calculating the axial distribution characteristics of the fragment velocity.For this type of warhead,the simulation of the dispersion characteristics of the detonation products at different positions shows that the detonation products at the ends have a much larger axial velocity than those in the middle,and the detonation products have a greater axial dispersion velocity when they are closer to the central axis.The loading process and the fragment velocity vary with the axial position for both casing layers,and the total velocity of the fragments is the vector sum of the radial velocity and the axial velocity.At the same axial position,the acceleration time of the inner casing is greater than that of the outer casing.For the same casing,the fragments generated at the ends have a longer acceleration time than the fragments from the middle.The proposed formula is validated with the X-ray radiography results of the four warheads previously tested experimentally and the 3D smoothedparticle hydrodynamics numerical simulation results of several series of new warheads with different configurations.The formula can accurately and reliably calculate the fragment velocity when the lengthto-diameter ratio of the charge is greater than 1.5 and the thickness of the casing is less than 20%its inner radius.This work thus provides a key reference for the theoretical analysis and the design of warheads with multiple casings.

关键词： Double casing warhead Sandwiched charge Fragment velocity Rarefaction wave Gurney formula Explosive loading

Energy transfer, anticounterfeiting, white light emission and sensing in fine-regulating series of lanthanide metal-organic frameworks

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Journal of Rare Earths 2024年第3期42卷 446-454,I0001页

作者： Juanjuan Xue yao wang Guoping Yang yaoyu wang Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Shaanxi Key Laboratory of Physico-Inorganic ChemistryCollege of Chemistry&Materials ScienceNorthwest UniversityXi'an710127China

Three lanthanide ions and a rigid(1,1'-biphenyl)-2,4,6-tricarboxylic acid(H_(3)bptc) ligand led to the isostructural lanthanide metal-organic frameworks(Ln-MOFs) {[Ln(bptc)(H_(2)O)_(3)]·3H_(2)O}_n(Lnbptc, Ln = Eu,Tb, Gd, Eu_(x)Tb_(1—x), Eu_(x)Gd_(1-x), Tb_(x)Gd_(1-x), and Eu_(0.12)Tb_(0.52)Gd_(0.36)). The density functional theory(DFT) and time-dependent DFT calculation were expanded on H_3bptc, which point to the occurrence of “antenna effect”. The minor diameter samples of Eubptc, Tbbptc, and Gdbptc can also be attained via the microwave synthesis and employed for handwriting anticounterfeiting. Interestingly, the typical red emission of Eu^(3+) and green emission of Tb~(3+) could be fine-tuned by Gd^(3+) via chemical mixing to be full-color emissions bimetallic doped Eu_(x)Tb_(1-x)bptc, Eu_(x)Gd_(1-x)bptc, and Tb_(x)Gd_(1-x)bptc. The above synthetic bimetallic MOFs can be fixed in positioning boxes of quick response(QR) codes with diverse emission for anticounterfeiting. The message can be decoded under the irradiation of 365 nm ultraviolet lamp while invisible in the daylight. Notably, the trimetallic doped Eu_(0.12)Tb_(0.52)Gd_(0.36)bptc emits white light with the CIE color coordinate(0.34, 0.34). Furthermore, Tbbptc is demonstrated to be a sensitive probe toward nitrobenzene and acetone with multiple mechanisms.

关键词： Metal-organic frameworks Anticounterfeiting White light-emitting Sensing Rare earths

Expression Recognition Method Based on Convolutional Neural Network and Capsule Neural Network

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Computers, Materials & Continua 2024年第4期79卷 1659-1677页

作者： Zhanfeng wang Lisha yao School of Computer Science and Artificial Intelligence Chaohu UniversityHefei238000China School of Big Data and Artificial Intelligence Anhui Xinhua UniversityHefei230088China

Convolutional neural networks struggle to accurately handle changes in angles and twists in the direction of images,which affects their ability to recognize patterns based on internal feature levels. In contrast, CapsNet overcomesthese limitations by vectorizing information through increased directionality and magnitude, ensuring that spatialinformation is not overlooked. Therefore, this study proposes a novel expression recognition technique calledCAPSULE-VGG, which combines the strengths of CapsNet and convolutional neural networks. By refining andintegrating features extracted by a convolutional neural network before introducing theminto CapsNet, ourmodelenhances facial recognition capabilities. Compared to traditional neural network models, our approach offersfaster training pace, improved convergence speed, and higher accuracy rates approaching stability. Experimentalresults demonstrate that our method achieves recognition rates of 74.14% for the FER2013 expression dataset and99.85% for the CK+ expression dataset. By contrasting these findings with those obtained using conventionalexpression recognition techniques and incorporating CapsNet’s advantages, we effectively address issues associatedwith convolutional neural networks while increasing expression identification accuracy.

关键词： Expression recognition capsule neural network convolutional neural network

Icariin attenuates vascular endothelial dysfunction by inhibiting inflammation through GPER/Sirt1/HMGB1 signaling pathway in type 1 diabetic rats

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Chinese Journal of Natural Medicines 2024年第4期22卷 293-306页

作者： yao Wenhui TAO Rongpin wang Kai DING Xuansheng School of Basic Medicine and Clinical Pharmacy China Pharmaceutical UniversityNanjing211198China

Icariin, a flavonoid glycoside, is extracted from Epimedium. This study aimed to investigate the vascular protective effects of icariin in type 1 diabetic rats by inhibiting high-mobility group box 1 (HMGB1)-related inflammation and exploring its potential mechanisms. The impact of icariin on vascular dysfunction was assessed in streptozotocin (STZ)-induced diabetic rats through vascular reactivity studies. Western blotting and immunofluorescence assays were performed to measure the expressions of target proteins. The release of HMGB1 and pro-inflammation cytokines were measured by enzyme-linked immunosorbent assay (ELISA). The results revealed that icariin administration enhanced acetylcholine-induced vasodilation in the aortas of diabetic rats. It also notably reduced the release of pro-inflammatory cytokines, including interleukin-8 (IL-8), IL-6, IL-1β, and tumor necrosis factor-alpha (TNF-α) in diabetic rats and high glucose (HG)-induced human umbilical vein endothelial cells (HUVECs). The results also unveiled that the pro-inflammatory cytokines in the culture medium of HUVECs could be increased by rHMGB1. The increased release of HMGB1 and upregulated expressions of HMGB1-related inflammatory factors, including advanced glycation end products (RAGE), Toll-like receptor 4 (TLR4), and phosphorylated p65 (p-p65) in diabetic rats and HG-induced HUVECs, were remarkably suppressed by icariin. Notably, HMGB1 translocation from the nucleus to the cytoplasm in HUVECs under HG was inhibited by icariin. Meanwhile, icariin could activate G protein-coupled estrogen receptor (GPER) and sirt1. To explore the role of GPER and Sirt1 in the inhibitory effect of icariin on HMGB1 release and HMGB-induced inflammation, GPER inhibitor and Sirt1 inhibitor were used in this study. These inhibitors diminished the effects of icariin on HMGB1 release and HMGB1-induced inflammation. Specifically, the GPER inhibitor also negated the activation of Sirt1 by icariin. These findings suggest that icariin activates GPER and increases the exp

关键词： Icariin Diabetes Inflammation Vascular endothelial dysfunction GPER HMGB1

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental science.Therefore,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of catalysts.Although previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis methods.Here,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed catalysts.We also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and thermocatalysis.Finally,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

Lipid phosphorylation by a diacylglycerol kinase suppresses ABA biosynthesis to regulate plant stress responses

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Molecular Plant 2024年第2期17卷 342-358页

作者： Jianwu Li Shuaibing yao Sang-Chul Kim Xuemin wang Department of Biology University of Missouri-St.LouisSt.LouisMO 63121USA Donald Danforth Plant Science Center St.LouisMO 63132USA

Lipid phosphorylation by diacylglycerol kinase(DGK)that produces phosphatidic acid(PA)plays important roles in various biological processes,including stress responses,but the underlying mechanisms remain elusive.Here,we show that DGK5 and its lipid product PA suppress ABA biosynthesis by interacting withABA-DEFICIENT2(ABA2),a key ABA biosynthesis enzyme,to negatively modulate plant responseto abiotic stress tested in Arabidopsis thaliana.Loss of DGK5 function rendered plants less damaged,whereas overexpression(OE)of DGK5 enhanced plant damage to water and salt stress.The dgk5 mutant plants exhibited decreased total cellular and nuclear levels of PA with increased levels of diacylglycerol,whereas DGK5-OE plants displayed the opposite effect.Interestingly,we found that both DGK5 and PA bind to the ABA-synthesizing enzyme ABA2 and suppress its enzymatic activity.Consistently,the dgk5 mutant plants exhibited increased levels of ABA,while DGK5-OE plants showed reduced ABA levels.In addition,we showed that both DGK5 and ABA2 are detected in and outside the nuclei,and loss of DGK5 function decreased the nuclear association of ABA2.We found that both DGK5 activity and PA promote nuclear association of ABA2.Taken together,these results indicate that both DGK5 and PA interact with ABA2 to inhibit its enzymatic activity and promote its nuclear sequestration,thereby sup-pressing ABA production in response to abiotic stress.Our study reveals a sophisticated mechanism by which DGK5 and PA regulate plant stress responses.

关键词： diacylglycerol kinase phosphatidic acid diacylglycerol lipid signaling stress responses lipid-protein binding protein-protein interaction Arabidopsis

12.6μm-Thick Asymmetric Composite Electrolyte with Superior Interfacial Stability for Solid-State Lithium-Metal Batteries

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Nano-Micro Letters 2024年第9期16卷 397-409页

作者： Zheng Zhang Jingren Gou Kaixuan Cui Xin Zhang Yujian yao Suqing wang Haihui wang Beijing Key Laboratory for Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510000People’s Republic of China

Solid-state lithium metal batteries(SSLMBs)show great promise in terms of high-energy-density and high-safety performance.However,there is an urgent need to address the compatibility of electrolytes with high-voltage cathodes/Li anodes,and to minimize the electrolyte thickness to achieve highenergy-density of SSLMBs.Herein,we develop an ultrathin(12.6μm)asymmetric composite solid-state electrolyte with ultralight areal density(1.69 mg cm^(−2))for SSLMBs.The electrolyte combining a garnet(LLZO)layer and a metal organic framework(MOF)layer,which are fabricated on both sides of the polyethylene(PE)separator separately by tape casting.The PE separator endows the electrolyte with flexibility and excellent mechanical properties.The LLZO layer on the cathode side ensures high chemical stability at high voltage.The MOF layer on the anode side achieves a stable electric field and uniform Li flux,thus promoting uniform Li^(+)deposition.Thanks to the well-designed structure,the Li symmetric battery exhibits an ultralong cycle life(5000 h),and high-voltage SSLMBs achieve stable cycle performance.The assembled pouch cells provided a gravimetric/volume energy density of 344.0 Wh kg^(−1)/773.1 Wh L^(−1).This simple operation allows for large-scale preparation,and the design concept of ultrathin asymmetric structure also reveals the future development direction of SSLMBs.

关键词： Solid-state lithium metal batteries Composite solid-state electrolyte Ultrathin asymmetric structure Pouch cells

A SCALAR AUXILIARY VARIABLE (SAV) FINITE ELEMENT NUMERICAL SCHEME FOR THE CAHN-HILLIARD-HELE-SHAW SYSTEM WITH DYNAMIC BOUNDARY CONDITIONS

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Journal of Computational Mathematics 2024年第2期42卷 544-569页

作者： Changhui yao Fengdan Zhang Cheng wang School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China Department of Mathematics University of MassachusettsNorth DartmouthMA 02747USA

In this paper,we consider the Cahn-Hilliard-Hele-Shaw(CHHS)system with the dynamic boundary conditions,in which both the bulk and surface energy parts play important roles.The scalar auxiliary variable approach is introduced for the physical system;the mass conservation and energy dissipation is proved for the CHHS system.Subsequently,a fully discrete SAV finite element scheme is proposed,with the mass conservation and energy dissipation laws established at a theoretical level.In addition,the convergence analysis and error estimate is provided for the proposed SAV numerical scheme.

关键词： Cahn-Hilliard-Hele-Shaw system Dynamic boundary conditions Bulk energy and surface energy Scalar auxiliary variable formulation Energy stability Convergence analysis

Tau Accumulation in the Spinal Cord Contributes to Chronic Inflammatory Pain by Upregulation of IL-1βand BDNF

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Neuroscience Bulletin 2024年第4期40卷 466-482页

作者： Shuxia Zhang Yeru Chen Yongjie wang Hongwei wang Dandan yao Gang Chen Department of Anesthesiology School of MedicineSir Run Run Shaw HospitalZhejiang UniversityHangzhou310016China Key Laboratory of Elemene Anti-Cancer Medicine of Zhejiang Province and Holistic Integrative Pharmacy Institutes Hangzhou Normal UniversityHangzhou311121China Engineering Laboratory of Development and Application of Traditional Chinese Medicine from Zhejiang Province Holistic Integrative Pharmacy InstitutesHangzhou Normal UniversityHangzhou311121China

Microtubule-associated protein Tau is responsible for the stabilization of neuronal microtubules under normal physiological conditions.Much attention has been focused on Tau’s contribution to cognition,but little research has explored its role in emotions such as pain,anxiety,and depression.In the current study,we found a significant increase in the levels of p-Tau(Thr231),total Tau,IL-1β,and brain-derived neurotrophic factor(BDNF)on day 7 after complete Freund's adjuvant(CFA)injection;they were present in the vast majority of neurons in the spinal dorsal horn.Microinjection of Mapt-shRNA recombinant adeno-associated virus into the spinal dorsal cord alleviated CFA-induced inflammatory pain and inhibited CFA-induced IL-1βand BDNF upregulation.Importantly,Tau overexpression was sufficient to induce hyperalgesia by increasing the expression of IL-1βand BDNF.Furthermore,the activation of glycogen synthase kinase 3 beta partly contributed to Tau accumulation.These findings suggest that Tau in the dorsal horn could be a promising target for chronic inflammatory pain therapy.

关键词： Tau Inflammatory pain IL-1β BDNF