全文获取类型
收费全文 | 653篇 |
免费 | 54篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 7篇 |
综合类 | 1篇 |
化学工业 | 236篇 |
金属工艺 | 50篇 |
机械仪表 | 26篇 |
建筑科学 | 16篇 |
能源动力 | 52篇 |
轻工业 | 69篇 |
水利工程 | 7篇 |
石油天然气 | 3篇 |
无线电 | 37篇 |
一般工业技术 | 113篇 |
冶金工业 | 26篇 |
原子能技术 | 3篇 |
自动化技术 | 62篇 |
出版年
2023年 | 12篇 |
2022年 | 20篇 |
2021年 | 41篇 |
2020年 | 26篇 |
2019年 | 31篇 |
2018年 | 32篇 |
2017年 | 42篇 |
2016年 | 37篇 |
2015年 | 23篇 |
2014年 | 20篇 |
2013年 | 59篇 |
2012年 | 34篇 |
2011年 | 51篇 |
2010年 | 32篇 |
2009年 | 37篇 |
2008年 | 39篇 |
2007年 | 32篇 |
2006年 | 23篇 |
2005年 | 16篇 |
2004年 | 10篇 |
2003年 | 4篇 |
2002年 | 11篇 |
2001年 | 6篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 11篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 6篇 |
1994年 | 8篇 |
1993年 | 3篇 |
1992年 | 8篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1978年 | 3篇 |
排序方式: 共有708条查询结果,搜索用时 15 毫秒
1.
The thermodynamics modeling of a Reiner–Philippoff-type fluid is essential because it is a complex fluid with three distinct probable modifications. This fluid model can be modified to describe a shear-thinning, Newtonian, or shear-thickening fluid under varied viscoelastic conditions. This study constructs a mathematical model that describes a boundary layer flow of a Reiner–Philippoff fluid with nonlinear radiative heat flux and temperature- and concentration-induced buoyancy force. The dynamical model follows the usual conservation laws and is reduced through a nonsimilar group of transformations. The resulting equations are solved using a spectral-based local linearization method, and the accuracy of the numerical results is validated through the grid dependence and convergence tests. Detailed analyses of the effects of specific thermophysical parameters are presented through tables and graphs. The study reveals, among other results, that the buoyancy force, solute and thermal expansion coefficients, and thermal radiation increase the overall wall drag, heat, and mass fluxes. Furthermore, the study shows that amplifying the space and temperature-dependent heat source parameters allows fluid particles to lose their cohesive force and, consequently, maximize flow and heat transfer. 相似文献
2.
3.
Hashem O. Alsaab Alanoud S. Al-Hibs Rami Alzhrani Khawlah K. Alrabighi Aljawharah Alqathama Akram Alwithenani Atiah H. Almalki Yusuf S. Althobaiti 《International journal of molecular sciences》2021,22(4)
Angiogenesis is one of the hallmarks of cancer. Several studies have shown that vascular endothelium growth factor (VEGF) plays a leading role in angiogenesis progression. Antiangiogenic medication has gained substantial recognition and is commonly administered in many forms of human cancer, leading to a rising interest in cancer therapy. However, this treatment method can lead to a deteriorating outcome of resistance, invasion, distant metastasis, and overall survival relative to its cytotoxicity. Furthermore, there are significant obstacles in tracking the efficacy of antiangiogenic treatments by incorporating positive biomarkers into clinical settings. These shortcomings underline the essential need to identify additional angiogenic inhibitors that target numerous angiogenic factors or to develop a new method for drug delivery of current inhibitors. The great benefits of nanoparticles are their potential, based on their specific properties, to be effective mechanisms that concentrate on the biological system and control various important functions. Among various therapeutic approaches, nanotechnology has emerged as a new strategy for treating different cancer types. This article attempts to demonstrate the huge potential for targeted nanoparticles and their molecular imaging applications. Notably, several nanoparticles have been developed and engineered to demonstrate antiangiogenic features. This nanomedicine could effectively treat a number of cancers using antiangiogenic therapies as an alternative approach. We also discuss the latest antiangiogenic and nanotherapeutic strategies and highlight tumor vessels and their microenvironments. 相似文献
4.
Yavuz Emre Arslan Yusuf Furkan Galata Tugba Sezgin Arslan Burak Derkus 《Journal of materials science. Materials in medicine》2018,29(8):127
In this study, we aimed at fabricating decellularized bovine myocardial extracellular matrix-based films (dMEbF) for cardiac tissue engineering (CTE). The decellularization process was carried out utilizing four consecutive stages including hypotonic treatment, detergent treatment, enzymatic digestion and decontamination, respectively. In order to fabricate the dMEbF, dBM were digested with pepsin and gelation process was conducted. dMEbF were then crosslinked with N-hydroxysuccinimide/1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide (NHS/EDC) to increase their durability. Nuclear contents of native BM and decellularized BM (dBM) tissues were determined with DNA content analysis and agarose-gel electrophoresis. Cell viability on dMEbF for 3rd, 7th, and 14th days was assessed by MTT assay. Cell attachment on dMEbF was also studied by scanning electron microscopy. Trans-differentiation capacity of human adipose-derived mesenchymal stem cells (hAMSCs) into cardiomyocyte-like cells on dMEbF were also evaluated by histochemical and immunohistochemical analyses. DNA contents for native and dBM were, respectively, found as 886.11?±?164.85 and 47.66?±?0.09?ng/mg dry weight, indicating a successful decellularization process. The results of glycosaminoglycan and hydroxyproline assay, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), performed in order to characterize the extracellular matrix (ECM) composition of native and dBM tissue, showed that the BM matrix was not damaged during the proposed method. Lastly, regarding the histological study, dMEbF not only mimics native ECM, but also induces the stem cells into cardiomyocyte-like cells phenotype which brings it the potential of use in CTE. 相似文献
5.
Oguzhan Oguz Nicolas Candau Adrien Demongeot Mehmet Kerem Citak Fatma Nalan Cetin Grégory Stoclet Véronique Michaud Yusuf Z. Menceloglu 《Polymer Engineering and Science》2021,61(4):1028-1040
There is currently considerable interest in developing stiff, strong, tough, and heat resistant poly(lactide) (PLA) based materials with improved melt elasticity in response to the increasing demand for sustainable plastics. However, simultaneous optimization of stiffness, strength, and toughness is a challenge for any material, and commercial PLA is well-known to be inherently brittle and temperature-sensitive and to show poor melt elasticity. In this study, we report that high-shear mixing with cellulose nanocrystals (CNC) leads to significant improvements in the toughness, heat resistance, and melt elasticity of PLA while further enhancing its already outstanding room temperature stiffness and strength. This is evidenced by (i) one-fold increase in the elastic modulus (6.48 GPa), (ii) 43% increase in the tensile strength (87.1 MPa), (iii) one-fold increase in the strain at break (∼6%), (iv) two-fold increase in the impact strength (44.2 kJ/m2), (v) 113-fold increase in the storage modulus at 90°C (787.8 MPa), and (vi) 103-fold increase in the melt elasticity at 190°C and 1 rad/s (∼105 Pa) via the addition of 30 wt% CNC. It is hence possible to produce industrially viable, stiff, strong, tough, and heat resistant green materials with improved melt elasticity through high-shear mixing. 相似文献
6.
David J. Banner Emre Firlar Pavel Rehak Abhijit H. Phakatkar Tara Foroozan Jodi K. Osborn Lioudmila V. Sorokina Surya Narayanan Talia Tahseen Yusuf Baggia Petr Král Tolou Shokuhfar Reza Shahbazian-Yassar 《Advanced functional materials》2021,31(18):2007736
Calcium oxalate (CaOx) is the major phase in kidney stones and the primary calcium storage medium in plants. CaOx can form crystals with different lattice types, water contents, and crystal structures. However, the conditions and mechanisms leading to nucleation of particular CaOx crystals are unclear. Here, liquid-cell transmission electron microscopy and atomistic molecular dynamics simulations are used to study in situ CaOx nucleation at different conditions. The observations reveal that rhombohedral CaOx monohydrate (COM) can nucleate via a classical pathway, while square COM can nucleate via a non-classical multiphase pathway. Citrate, a kidney stone inhibitor, increases the solubility of calcium by forming calcium-citrate complexes and blocks oxalate ions from approaching calcium. The presence of multiple hydrated ionic species draws additional water molecules into nucleating CaOx dihydrate crystals. These findings reveal that by controlling the nucleation pathways one can determine the macroscale crystal structure, hydration state, and morphology of CaOx. 相似文献
7.
Predicting catastrophic temperature changes based on past events via a CNN-LSTM regression mechanism
Yusuf Syed Adnan Alshdadi Abdulrahman A. Alassafi Madini O. AlGhamdi Rayed Samad Abdul 《Neural computing & applications》2021,33(15):9775-9790
Neural Computing and Applications - The modelling and prediction of extreme temperature changes in enclosed compartments is a domain with applications ranging from residential fire alarms,... 相似文献
8.
9.
10.