全文获取类型
收费全文 | 322篇 |
免费 | 15篇 |
专业分类
电工技术 | 3篇 |
综合类 | 1篇 |
化学工业 | 120篇 |
金属工艺 | 2篇 |
机械仪表 | 6篇 |
建筑科学 | 11篇 |
能源动力 | 22篇 |
轻工业 | 35篇 |
水利工程 | 7篇 |
石油天然气 | 2篇 |
无线电 | 20篇 |
一般工业技术 | 42篇 |
冶金工业 | 11篇 |
原子能技术 | 1篇 |
自动化技术 | 54篇 |
出版年
2024年 | 2篇 |
2023年 | 4篇 |
2022年 | 16篇 |
2021年 | 19篇 |
2020年 | 22篇 |
2019年 | 26篇 |
2018年 | 17篇 |
2017年 | 19篇 |
2016年 | 17篇 |
2015年 | 14篇 |
2014年 | 13篇 |
2013年 | 26篇 |
2012年 | 19篇 |
2011年 | 18篇 |
2010年 | 11篇 |
2009年 | 8篇 |
2008年 | 6篇 |
2007年 | 10篇 |
2006年 | 7篇 |
2005年 | 4篇 |
2004年 | 5篇 |
2003年 | 1篇 |
2002年 | 6篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有337条查询结果,搜索用时 0 毫秒
81.
Zaidatul Akmal Othman Zaida Zakaria Joseph Bagi Suleiman Khairul Mohd Fadzli Mustaffa Nur Asyilla Che Jalil Wan Syaheedah Wan Ghazali Ninie Nadia Zulkipli Mahaneem Mohamed 《International journal of molecular sciences》2022,23(18)
Oxidative stress contributes to major complications of obesity. This study intended to identify whether orlistat could mitigate myocardial damage in obese animal models. The tested rats were divided into two groups and fed either with normal chow (n = 6 per group) or with a high-fat diet (HFD) for 6 weeks to induce obesity (n = 12 per group). Obese rats were further subjected to treatment either with distilled water (OB group) or orlistat 10 mg/kg/day (OB + OR group). Key indices of oxidative stress, inflammation, and apoptosis were assessed using an immunohistochemical-based technique and real-time PCR. The OB group showed significant increases of oxidative stress markers (TBARs and PCO), with significant decreases of anti-oxidant markers (Nrf2, SOD, CAT, and GPx). Furthermore, mRNA expression of pro-inflammatory markers (TNF-α and NF-κβ) and pro-apoptosis markers (Bax, Caspase-3, Caspase-8, and Caspase-9) were significantly upregulated in the OB group. Obese rats developed pathological changes of myocardial damages as evidenced by the presence of myocardial hypertrophy and inflammatory cells infiltration. Orlistat dampened the progression of myocardial damage in obese rats by ameliorating the oxidative stress, and by inhibiting NF-κβ pathway and caspase-dependent cell apoptosis. Our study proposed that orlistat could potentially mitigate oxidative stress-linked myocardial damage by mitigating inflammation and apoptosis, thus rationalizing its medical usage. 相似文献
82.
83.
Fatima El Bachraoui Zakaria Chchiyai Youssef Tamraoui Hassan El Moussaoui Jones Alami Bouchaib Manoun 《中国稀土学报(英文版)》2022,40(4):652-659
Structural, optical and magnetic properties are reported for new synthesized perovskite materials. Ba0.3La0.7Ti0.3Fe0.7O3 and Ba0.1La0.9Ti0.1Fe0.9O3 compositions were prepared via solid state reaction. X-ray analysis confirms that both compositions show feature of perovskite structure. Rietveld refinement method was used to confirm the phase formation and investigate the structure and space group. The study demonstrates the formation of orthorhombic structure with Pnma space group for Ba0.3La0.7Ti0.3Fe0.7O3 while the composition Ba0.1La0.9Ti0.1Fe0.9O3 structure adopts Pbnm symmetry. UV–vis spectroscopy measurements show very broad and intense UV–visible light absorption, the estimated band gap ranges between 2.07 and 2.15 eV. Magnetic measurements were carried out for the compositions Ba0.3La0.7Ti0.3Fe0.7O3 and Ba0.1La0.9Ti0.1Fe0.9O3. The hysteresis loops of both samples at 300 and 10 K show a strong ferromagnetic behavior. The temperature dependent magnetization at 0.05 T under field-cooled (FC) and zero field cooled (ZFC) modes shows magnetic frustration or spin glass-like behavior. 相似文献
84.
Zakaria M. Sawan Abd El-Hamid A. El-Farra Sania Abd El-Latif 《Journal of the American Oil Chemists' Society》1988,65(6):948-951
Two experiments were carried out at our research center during the 1981 and 1982 seasons on cotton cultivar Giza 75 (Gossypium barbadense L.) to investigate the influence of nitrogen fertilization rates (72, 144 or 216 kg/ha.), phosphorus levels (36 or 72 kg P2O5/ha.) and three growth regulators (IAA, IBA or NAA) applied to cotton plants at 10 ppm and sprayed three times (70, 85 and
100 days after sowing) on protein and oil yields, and oil properties. A randomized complete block design with four replications
treatment combinations was used.
The combined analysis of the results of the two seasons revealed that yields of cottonseed, oil and protein increased by raising
nitrogen and phosphorus levels and under the application of growth regulators. Seed index increased by raising the added nitrogen
and the applied growth regulants. No detectable effect of phosphorus levels was observed. The seed oil percentage decreased,
although the protein percentage increased, when the nitrogen application rate was raised. Application of growth regulators
and a high phosphorus level increased the seed oil percentage, but the seed protein percentage was not affected. The seed
oil properties, i.e., acidity, saponification and iodine values, tended to decrease slightly by increasing the nitrogen application
rate and the application of growth substances, but the trend reversed when the phosphorus level was raised. The mean values
of oil specific gravity and refractive index did not show any definite responses. 相似文献
85.
User-driven RFID applications and challenges 总被引:1,自引:1,他引:0
Aikaterini Mitrokotsa Quan Z. Sheng Zakaria Maamar 《Personal and Ubiquitous Computing》2012,16(3):223-224
86.
This paper investigates low velocity impact involving a glass fiber‐reinforced polyamide engine oil pan as part of a complete new development of thermoplastic components. The assessment of the impact resistance has driven the need to employ LS DYNA for finite element modeling in order to benchmark and predict the strength and fracture behavior of stressed plastic parts. In order to develop a reliable predictive capability and to validate simulations, complete components were manufactured by injection molding techniques for the experimental samples. Low velocity impact investigations were carried out using a gas gun and a falling weight tester in order to simulate impact events to which the oil pan is subjected whilst in operational service. This was intended to point out damage tolerance and failure mechanisms likely to occur in the structure. The study results show the significant contribution of the design in terms of shock absorption. Specific oil pan design with protective ribbing combined with a superior material considerably improves the impact resistance. The paper provides results and discussions on experimental and finite element analysis investigations before concluding with some remarks. 相似文献
87.
Eltai Nahla O. Mahmoud Nouf N. Zakaria Zain Z. Abdelrahman Hana Moustafa Ala-Eddin Al Al-Asmakh Maha 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(7):2527-2537
Journal of Inorganic and Organometallic Polymers and Materials - Gold nanorods (AuNRs) were synthesized by the seed-mediated wet chemical method using a binary surfactant system. AuNRs were... 相似文献
88.
Lau Kam Sheng Chin Siew Xian Khiew Poi Sim Zakaria Sarani Yin Michelle Lee Jia Key Kelly Hong Mun Chia Chin Hua 《Journal of Porous Materials》2022,29(2):609-619
Journal of Porous Materials - In this study, a fast and simple dissolution and coagulation method was adopted to produce polyethylenimine (PEI)-incorporated chitosan beads. The beads were... 相似文献
89.
Zamiri R Zakaria A Ahangar HA Sadrolhosseini AR Mahdi MA 《International journal of molecular sciences》2010,11(11):4764-4770
In this study we used a laser ablation technique for preparation of silver nanoparticles. The fabrication process was carried out by ablation of a silver plate immersed in palm oil. A pulsed Nd:YAG laser at a wavelength of 1064 nm was used for ablation of the plate at different times. The palm coconut oil allowed formation of nanoparticles with very small and uniform particle size, which are dispersed very homogeneously within the solution. The obtained particle sizes for 15 and 30 minute ablation times were 2.5 and 2 nm, respectively. Stability study shows that all of the samples remained stable for a reasonable period of time. 相似文献
90.
This paper investigates the influence of liquid fuel presence on the autoignition of n-heptane/air mixtures over a wide range of conditions encountered in internal combustion engines. To this end, evaporating droplet physics and skeletal chemistry mechanisms are simultaneously solved considering a homogeneous constant-pressure reactor. A skeletal mechanism is introduced to account for specific kinetics behavior in the Negative Temperature Coefficient (NTC) region. The impact of mass and heat source terms during evaporation is emphasized by comparing a two-phase flow scenario with a purely gaseous case. The competition between fuel vapor availability and the evaporation-induced gas temperature decrease is specific to two-phase flow autoignition. On the one hand, droplet evaporation delay restricts the gaseous local fuel/air equivalence ratio and consequently the kinetics runaway. On the other hand, temperature reduction due to evaporation may either reduce or enhance chemical reactivity, depending on the local thermodynamic conditions lying either inside or outside the NTC region. By simultaneously accounting for evaporation source terms and skeletal chemistry, we can reproduce the already experimentally observed transformation of the NTC region into a Zero Temperature Coefficient (ZTC) region depending on thermodynamic conditions and droplet size. The ZTC phenomenon appears when combustion heat-release starts before complete droplet evaporation. Since the ZTC behavior can be captured using the point source approach, in which droplets are considered only as zero-dimensional source terms of mass and energy, the present results pave the way for future exploration of NTC chemistry in sprays with a direct numerical simulation of discrete particles considering detailed chemistry and turbulent flows. 相似文献