检索结果-南通市图书馆

Study of damage behavior and repair effectiveness of patch repaired carbon fiber laminate under quasi-static indentation loading

引用

Defence Technology（防务技术） 2024年第4期34卷 29-41页

作者： alok Kumar Chinmaya Kumar Sahoo A.Arockiarajan Department of Applied Mechanics Indian Institute of Technology MadrasChennai 600036India

Damage caused due to low-velocity impacts in composites leads to substantial deterioration in their residual strength and eventually provokes structural *** work presents an experimental investigation on the effects of different patch and parent laminate stacking sequences on the enhancement of impact strength of Carbon Fiber Reinforced Polymers(CFRP)composites by utilising the adhesively bonded external patch repair *** evolution study is also performed with the aid of Acoustic Emission(AE).Two different quasi-isotropic configurations were selected for the parent laminate,viz.,[45°/45°/0°/0°]s and[45°/0°/45°/0°]*** Static Indentation(QSI)test was performed on both the pristine laminates,and damage areas were detected by using the C-scan inspection *** laminates were repaired by using a single-sided patch of two different configurations,viz.,[45°/45°/45°/45°]and[45°/0°/0°/45°],and employing a circular plug to fill the damaged *** different combinations of repaired laminates with two configurations of each parent and patch laminate were produced,which were further subjected to the QSI *** results reveal the effectiveness of the repair method,as all the repaired laminates show higher impact resistance compared to the respective pristine *** of[45°/0°/0°/45°]configuration when repaired by taking[45°/45°/0°/0°]s and[45°/0°/45°/0°]s as parents exhibited 68%and 73%higher peak loads,respectively,than the respective pristine ***,parent and patch of configuration[45°/0°/45°/0°]s and[45°/0°/0°/45°],respectively,attain the highest peak load,whereas[45°/45°/0°/0°]s and[45°/45°/45°/45°]combinations possess the most gradual decrease in the load.

关键词： Carbon fiber reinforced polymers(CFRP) Quasi-isotropic laminate Quasi static indentation(QSI) Acoustic emission(AE) Composite repair

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An improved reverse time migration for subsurface imaging over complex geological structures:A numerical study

Energy Geoscience

引用

Energy Geoscience 2024年第2期5卷 290-297页

作者： alok Kumar Routa Priya Ranjan Monahty Department of Applied Geophysics IIT(ISM)DhanbadJharkhandIndia

In seismic exploration,it is a critical task to image and interpret different seismic signatures over complex geology due to strong lateral velocity contrast,steep reflectors,overburden strata and dipping *** understand the behavior of these seismic signatures,nowadays Reverse Time Migration(RTM)technique is used extensively by the oil&gas *** the extrapolation phase of RTM,the source wavefield needs to be saved,which needs high storage memory and large computing *** two are the main obstacles of RTM for production *** order to overcome these disadvantages,in this study,a second-generation improved RTM technique is *** this improved form,a shift operator is introduced at the time of imaging condition of RTM algorithm which is performed automatically both in space and time *** effort is made to produce a better-quality image by minimizing the computational time as well as numerical *** proposed method is applied over various benchmark models and validated by implementing over one field data set from the Jaisalmer Basin,*** the analysis,it is observed that the method consumes a minimum of 45%less storage space and reduce the execution time by 20%,as compared to conventional *** proposed RTM is found to work efficiently in comparison to the conventional RTM both in terms of imaging quality and minimization of numerical artefacts for all the benchmark models as well as field data.

关键词： Imaging condition Reverse time migration(RTM) Seismic imaging Velocity-depth model Wave propagation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Characterization and Propagation of Historical and Projected Droughts in the Umatilla River Basin, Oregon, USA

引用

Advances in Atmospheric Sciences 2024年第2期41卷 247-262,I0020-I0028页

作者： Sudip GAUTAM alok SAMANTARAY Meghna BABBAR-SEBENS Meenu RAMADAS School of Civil and Construction Engineering Oregon State UniversityCorvallisOR 97331USA School of Infrastructure Indian Institute of TechnologyBhubaneswarOdisha 752050India

Climate change is expected to have long-term impacts on drought and wildfire risks in Oregon as summers continue to become warmer and drier. This paper investigates the projected changes in drought characteristics and drought propagation in the Umatilla River Basin in northeastern Oregon for mid-century(2030–2059) and late-century(2070–2099) climate scenarios. Drought characteristics for projected climates were determined using downscaled CMIP5 climate datasets from ten climate models and Soil and Water Assessment Tool to simulate effects on hydrologic processes. Short-term(three months) drought characteristics(frequency, duration, and severity) were analyzed using four drought indices, including the Standardized Precipitation Index(SPI-3), Standardized Precipitation-Evapotranspiration Index(SPEI-3), Standardized Streamflow Index(SSI-3), and the Standardized Soil Moisture Index(SSMI-3). Results indicate that short-term meteorological droughts are projected to become more prevalent, with up to a 20% increase in the frequency of SPI-3drought events. Short-term hydrological droughts are projected to become more frequent(average increase of 11% in frequency of SSI-3 drought events), more severe, and longer in duration(average increase of 8% for short-term droughts).Similarly, short-term agricultural droughts are projected to become more frequent(average increase of 28% in frequency of SSMI-3 drought events) but slightly shorter in duration(average decrease of 4%) in the future. Historically, drought propagation time from meteorological to hydrological drought is shorter than from meteorological to agricultural drought in most sub-basins. For the projected climate scenarios, the decrease in drought propagation time will likely stress the timing and capacity of water supply in the basin for irrigation and other uses.

关键词： Umatilla drought SPI SPEI SSI SSMI

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Insight into Metabolomic Profiling of Tinospora cordifolia: Recent Advances and Future Perspectives of Quality Control

引用

World Journal of Traditional Chinese Medicine 2024年第2期10卷 137-148页

作者： Atiqul Islam C.Anurag Nazia Siddiqui Xianting Ding alok.shar.a College of Pharmacy JSS Academy of Technical EducationNoidaUttar PradeshIndia Department of Pharmaceutical Technology MIETMeerutUttar PradeshIndia Institute for Personalized Medicine School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina

The objective of this study was to offer a review of previous works on Tinospora cordifolia(TC) metabolomics with a highlight on the use of metabolomics in comparative evaluations between varieties and selection of optimum cultivation, collection, and extraction procedures, providing insights into pharmaceutical and food product quality monitoring. Scholarly databases were searched to gather relevant information on TC's therapeutic usefulness, phytoconstituent studies, metabolomics, and applications. Pub Chem was used to learn the structures of several of the metabolites. The various medicinal properties of TC were extensively researched. The most essential portions of the plant in Ayurvedic medicines are the stems. Bioactive phytochemicals such as steroidal lactones, alkaloids, diterpenoids, and phenolic compounds are present in the roots and leaves. Metabolomic analysis revealed that, in addition to the season and geographical region of the sample collected, the metabolite profiles of TC also depend on the parts of the plant taken as a sample and also the plant's stage of growth. The amounts of secondary metabolites differed between morpho/chemotypes within the TC species. Despite the fact that research on TC began several decades ago, the diversity of phytoconstituents was not appreciated because of a lack of reliable techniques for phytochemical fingerprinting. The uncovering of several novel metabolites was aided by advances in chromatography combined with mass spectrometry. To produce a full metabolomic profile, researchers used mutually complementary techniques. Following that, data analysis and searches against spectrum databases allowed for signal annotation and interpretation of metabolites in large quantities without separating them separately. The current review includes a critical assessment of metabolomic data and an overview of the technique's various applications. It is vital to establish the metrics of quality control of herbal medicines in order to

关键词： Analytical tools metabolomics quality control secondary metabolites Tinospora cordifolia

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Lipid-nanoparticle-enabled nucleic acid therapeutics for liver disorders

引用

Acta Pharmaceutica Sinica B 2024年第7期14卷 2885-2900页

作者： Porkizhi Arjunan Durga Kathirvelu Gokulnath Mahalingam Ashish Kumar Goel Uday George Zacharaiah alok Srivastava Srujan Marepally Center for Stem Cell Research(A Unit of inStem Bengaluru)Christian Medical College CampusBagayamVellore 632002Tamil NaduIndia Manipal academy for higher education Mangalore 576104KarnatakaIndia Department of Hematology Christian Medical College&HospitalVellore 632004Tamil NaduIndia Department of Hepatology Christian Medical College&HospitalVellore 632004Tamil NaduIndia

Inherited genetic disorders of the liver pose a significant public health *** transplantation is often limited by the availability of donor livers and the exorbitant costs of immunosuppressive *** overcome these limitations,nucleic acid therapy provides a hopeful alternative that enables gene repair,gene supplementation,and gene silencing with suitable *** viral vectors are the most efficient and preferred for gene therapy,pre-existing immunity debilitating immune responses limit their *** a potential alternative,lipid nanoparticle-mediated vectors are being explored to deliver multiple nucleic acid forms,including pDNA,mRNA,siRNA,and ***,we discuss the broader applications of lipid nanoparticles,from protein replacement therapy to restoring the disease mechanism through nucleic acid delivery and gene editing,as well as multiple preclinical and clinical studies as a potential alternative to liver transplantation.

关键词： Lipid nanoparticle Liver disorders Gene therapy Gene editing Nucleic acid delivery pDNA mRNA siRNA ASO Clinical trials

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plant based metabolomics:a future prospective and versatile tool for metabolite databases of Curcuma longa

引用

未来食品学报(英文) 2024年第1期4卷 37-47页

作者： Shuvendhu Gupta Amrat Pal Singh Gurpreet Singh Xianting Ding alok.shar.a Department of Pharmacognosy ISF College of PharmacyMoga 142001India Department of Pharmaceutical Chemistry ISF College of PharmacyMoga 142001India School of Biomedical Engineering Med-X Research InstituteShanghai Jiao Tong UniversityShanghai 200030China

Sophisticated analytical instruments are used for quality evaluation and scientific validation to compliance the Sophisticated analytical instruments are used for quality evaluation and scientific validation to compliance the market ***,increase in demand of Curcuma longa has led to a high swing in small and medium food *** present review is devoted to an in-depth information on metabolite database of *** from different analytical techniques such as high-performance thin-layer chromatography(HPTLC),liquid chromatography-mass spectrometry,gas chromatography-mass spectrometry and nuclear magnetic *** work highlights different extraction methods,phytochemistry along with structure activity relationship,nutritional profiling,market viability and pharmacology of *** bioactives of *** depends on various factors such as plants growth,temperature,humidity,soil type,collection,drying and extraction *** factors can contribute in quality evaluation of the food supplements if need to be *** introduction of omics approaches can helpful to explore the quality and identification of potential lead of *** results could play an essential role in the area of food-phyto based ***,metabolomics techniques may provide a analytical platfom by combination of different"omics"data souces for future esearch to food sand herbal based products.

关键词： Curcuma longa Omics approaches Multidisciplinary method Quality control Metabolomics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

引用

Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled alok Timothy G.White Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluation of temperature dependent vortex pinning properties in strongly pinned YBa_(2)Cu_(3)O_(7-δ)thin films with Y_(2)BaCuO_(5)nanoinclusions

引用

Superconductivity 2024年第1期9卷 95-105页

作者： alok K.Jha Kaname Matsumoto Tomoya Horide Shrikant Saini Ataru Ichinose Paolo Mele Yutaka Yoshida Satoshi Awaji Department of Materials Science and Engineering Kyushu Institute of TechnologyTobata-kuKitakyushu 804-8550Japan Department of Mechanical and Control Engineering Kyushu Institute of TechnologyTobata-kuKitakyushu 804-8550Japan Central Research Institute of Electrical Power Industry YokosukaKanagawa 240-0196Japan College of Engineering-Innovative Global Program Shibaura Institute of TechnologyMinuma-kuSaitama 337-8570Japan Department of Energy Engineering and Science Nagoya UniversityChikusa-kuNagoya 464-8603Japan Institute for Materials Research Tohoku UniversityAoba-kuSendai 980-8577Japan

The pinning of quantized magnetic vortices in superconducting YBa_(2)Cu_(3)O_(7-δ)(YBCO or Y123)thin films with Y_(2)BaCuO_(5)(Y211)nanoinclusions have been investigated over wide temperature range(4.2-77 K).The concentration of Y211 nanoinclusions has been systematically varied inside YBCO thin films prepared by laser ablation technique using surface modified target *** pinning force density values(Fp∼0.5 TNm^(−3)at 4.2 K,9 T)have been observed for the YBCO film with moderate concentration of Y211 nanoinclusions(3.6 area%on ablation target).In addition,uniform enhancement in critical current density(J_(c))was observed in the angular dependent J_(c)measurement of YBCO+Y211 nanocomposite films.Y211 nanoinclusions have been found to be very efficient in pinning the quantized vortices thereby enhancing the in‐field J_(c)values over a wide range of *** the concentration of Y211 secondary phase into Y123 film matrix results into agglomeration of Y211 phase and observed as increased Y211 nanoparticle *** larger secondary phase nanoparticles are not as efficient pinning centers at lower temperatures as they are at higher temperatures due to substantial reduction of the coherence length at lower *** of the temperature dependence of J_(c)for YBCO+Y211 nanocomposite films has been conducted and possible vortex pinning mechanism in these nanocomposite films has been discussed.

关键词： YBCO thin film Critical current Vortex pinning Nanoscale APCs

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Refinement of the Proposed Gamma-Ray Burst Time Delay Model

引用

International Journal of Astronomy and Astrophysics 2024年第2期14卷 120-147页

作者： Godson Fortune Abbey Joseph Simfukwe Prospery Christopher Simpemba Saul Paul Phiri alok Srivastava Golden Gadzirayi Nyambuya Department of Physic School of Mathematics and Natural Sciences The Copperbelt University Kitwe Republic of Zambia Fundamental Theoretical and Research Group Department of Applied Physics Faculty of Applied Sciences National University of Science & Technology Bulawayo Republic of Zimbabwe

This paper is the second instalment in our study of the observed time delay in the arrival times of radio photons emanating from Gamma Ray Bursts (GRBs). The mundane assumption in contemporary physics as to the cause of these pondersome time delays is that they are a result of the photon being endowed with a non-zero mass. While we do not rule out the possibility of a non-zero mass for the photon, our working assumption is that the major cause of these time delays may very well be that these photons are travelling in a rarefied cosmic plasma in which the medium’s electrons interact with the electric component of the Photon, thus generating tiny currents that lead to dispersion, hence, a frequency-dependent speed of Light (FDSL). In the present instalment, we “improve” on the model presented in the first instalment by dropping the assumption that the resultant pairs of these radio photons leave the shock front simultaneously. The new assumption of a non-simultaneous— albeit systematic—emission of these photon pairs allows us to obtain a much more convincing and stronger correlation in the time delay. This new correlation allows us to build a unified model for the four GRBs in our sample using a relative distance correction mechanism. The new unified model allows us to obtain as our most significant result a value for the frequency equivalence of the interstellar medium (ISM)’s conductance ν* ~ 1.500 ± 0.009 Hzand also an independent distance measure to the GRBs where we obtain for our four GRB samples an average distance of: ~69.40 ± 0.10, 40.00 ± 0.00, 58.40 ± 0.40, and 86.00 ± 1.00 Mpc, for GRB 030329, 980425, 000418 and 021004 respectively.

关键词： Gamma-Ray Bursts (GRB) Photon Mass Plasma Time Delay Fireball Model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical profiling of bioactive compounds in the methanolic extract of wild leaf and callus of Vitex negundo using gas chromatographymass spectrometry

引用

World Journal of Experimental Medicine 2024年第1期14卷 78-87页

作者： Gunjan Garg alok Bharadwaj Shweta Chaudhary Veena Gupta School of Biotechnology Gautam Buddha UniversityGreater Noida 201312Uttar PradeshIndia Biotechnology GLA UniversityMathura 281406Uttar PradeshIndia Division of Germplasm Conservation Indian Council of Agricultural Research-National Bureau of Plant Genetic ResourcesNew Delhi 110012New DelhiIndia

BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug *** negundo(***),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional *** To determine the existence of therapeutic components in leaf and callus extracts from wild *** plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus *** growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS *** The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus *** plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,*** Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic *** acid was the most common constituent in all *** maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,*** findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to *** addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also *** these components were only available in callus formed in-vit

关键词： Leaf extracts Callus extracts Methanolic extract Octadecadienoic acid Hexadecanoic acid Methyl ester Gas chromatography-mass spectrometry analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：