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排序方式: 共有850条查询结果,搜索用时 31 毫秒
841.
In this paper the existence and uniqueness of different types of solutions to a class of semilinear retarded differential equations with nonlocal history conditions are obtained by a fixed point argument. Also finite dimensional approximation of these solutions in a Hilbert space is established. 相似文献
842.
Mathematical Programming - Branch-and-bound is the workhorse of all state-of-the-art mixed integer linear programming (MILP) solvers. These implementations of branch-and-bound typically use... 相似文献
843.
Gadge Sandhya Tamboli Ashif Shinde Manish Fouad Hassan Terashima Chiaki Chauhan Ratna Gosavi Suresh 《Journal of Solid State Electrochemistry》2023,27(8):2005-2015
Journal of Solid State Electrochemistry - The industrial revolution has raised major concern of environmental pollution, due to excess release of hazardous chemical, dyes, etc. into water bodies.... 相似文献
844.
845.
Khairnar Akshada Lohidasan Sathiyanarayanan Dubey Rahul Sankaran Sandeep 《平面色谱法杂志一现代薄层色谱法》2023,36(1):63-70
JPC – Journal of Planar Chromatography – Modern TLC - People all over the world are affected by the chronic, disabling autoimmune illness known as rheumatoid arthritis (RA). Herbal... 相似文献
846.
Ritesh Kumar Dubey Prabhat Mishra 《Numerical Methods for Partial Differential Equations》2023,39(1):108-132
It is well known that on uniform mesh classical higher order schemes for evolutionary problems yield an oscillatory approximation of the solution containing discontinuity or boundary layers. In this article, an entirely new approach for constructing locally adaptive mesh is given to compute nonoscillatory solution by representative “second” order schemes. This is done using modified equation analysis and a notion of data dependent stability of schemes to identify the solution regions for local mesh adaptation. The proposed algorithm is applied on scalar problems to compute the solution with discontinuity or boundary layer. Presented numerical results show underlying second order schemes approximate discontinuities and boundary layers without spurious oscillations. 相似文献
847.
Deepshikha Yadav Shilpi Verma Jyoti Choudhary Harleen Kaur Pratibha Tiwari Sandeep Singh Pallavi Kushwaha Premshankar K. Dubey Pranjal Chandra Surinder P. Singh 《Electroanalysis》2023,35(4):e202200286
Folic acid (FA) deficiency is associated with several clinical conditions such as megaloblastic anemia, neuropsychiatric, and pregnancy-related syndromes, this makes FA an important metabolite to be monitored. We have fabricated an electrochemical biosensor based on gold nanoparticles decorated molybdenum disulfide nanosheets (AuNPs−MoS2NSs) nanocomposite as a transducer matrix for specific and rapid electrochemical detection of FA. Differential pulse voltammetry (DPV) studies displayed a rapid analytical response of the fabricated AuNPs−MoS2NSs/GCE sensor probe towards FA in a wide concentration range of 0.001–100 μM with a very low detection limit of 0.72±0.03 nM. The selectivity of the fabricated sensor probe has been examined in the presence of interferents such as dopamine, uric acid, ascorbic acid, glucose, and urea. The clinical potential of the fabricated biosensor was established by monitoring FA in human serum samples. The developed AuNPs−MoS2NSs/GCE sensor probe showed high reproducibility and stability, indicating its promise for FA detection in clinical settings. 相似文献
848.
Polydimethylsiloxane (PDMS) based microfluidic devices have found increasing utility for electrophoretic and electrokinetic assays because of their ease of fabrication using replica molding. However, the fabrication of high-resolution molds for replica molding still requires the resource-intensive and time-consuming photolithography process, which precludes quick design iterations and device optimization. We here demonstrate a low-cost, rapid microfabrication process, based on electrohydrodynamic jet printing (EJP), for fabricating non-sacrificial master molds for replica molding of PDMS microfluidic devices. The method is based on the precise deposition of an electrically stretched polymeric solution of polycaprolactone in acetic acid on a silicon wafer placed on a computer-controlled motion stage. This process offers the high-resolution (order 10 m) capability of photolithography and rapid prototyping capability of inkjet printing to print high-resolution templates for elastomeric microfluidic devices within a few minutes. Through proper selection of the operating parameters such as solution flow rate, applied electric field, and stage speed, we demonstrate microfabrication of intricate master molds and corresponding PDMS microfluidic devices for electrokinetic applications. We demonstrate the utility of the fabricated PDMS microchips for nonlinear electrokinetic processes such as electrokinetic instability and controlled sample splitting in ITP. The ability to rapid prototype customized reusable master molds with order 10 m resolution within a few minutes can help in designing and optimizing microfluidic devices for various electrokinetic applications. 相似文献
849.
Manish K. Saraf Louis M. Wojcinski II Karen A. Kennedy Sylvain Gerard Paul A. Charpentier Joseph M. DeSimone George W. Roberts 《Macromolecular Symposia》2002,182(1):119-129
The surfactant-free precipitation polymerization of vinylidene fluoride (VF2) in supercritical carbon dioxide was studied in a continuous stirred autoclave. The polymerization temperature ranged from 65 to 85°C, the average residence time in the reactor varied from 10 to 50 min., and the pressure was between 210 and 305 bar. Diethyl peroxydicarbonate was used as the initiator. The fractional conversion of monomer varied from 7 to 26%, the number-average molecular weight of the polymer was between about 14,000 and 79,000, and the weight-average molecular weight was between about 21,000 and 700,000. In many cases, the polymer exhibited a bimodal molecular-weight distribution, especially at high monomer concentrations. 相似文献
850.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献