全文获取类型
收费全文 | 196篇 |
免费 | 7篇 |
国内免费 | 6篇 |
专业分类
化学 | 138篇 |
晶体学 | 2篇 |
力学 | 7篇 |
数学 | 40篇 |
物理学 | 22篇 |
出版年
2022年 | 11篇 |
2021年 | 11篇 |
2020年 | 10篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 14篇 |
2013年 | 8篇 |
2012年 | 13篇 |
2011年 | 12篇 |
2010年 | 14篇 |
2009年 | 9篇 |
2008年 | 3篇 |
2007年 | 8篇 |
2006年 | 12篇 |
2005年 | 7篇 |
2004年 | 2篇 |
2003年 | 6篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1984年 | 1篇 |
1979年 | 1篇 |
1978年 | 6篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1959年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有209条查询结果,搜索用时 31 毫秒
41.
42.
Amin Esfahani Luiz Gustavo Farah Hongwei Wang 《Nonlinear Analysis: Theory, Methods & Applications》2012
In this paper we prove local well-posedness in L2(R) and H1(R) for the generalized sixth-order Boussinesq equation utt=uxx+βuxxxx+uxxxxxx+(|u|αu)xx. Our proof relies in the oscillatory integrals estimates introduced by Kenig et al. (1991) [14]. We also show that, under suitable conditions, a global solution for the initial value problem exists. In addition, we derive the sufficient conditions for the blow-up of the solution to the problem. 相似文献
43.
Synergistic Effect of Bioactive Monoterpenes against the Mosquito,Culex pipiens (Diptera: Culicidae)
Amal Ramzi Abdelhakim El Ouali Lalami Saoussan Annemer Yassine Ez zoubi Amine Assouguem Mikhlid H. Almutairi Mohamed Kamel Ilaria Peluso Sezai Ercisli Abdellah Farah 《Molecules (Basel, Switzerland)》2022,27(13)
Mosquitoes represent one of the most important vectors and are responsible for the transmission of many arboviruses that affect human and animal health. The chemical method using synthetic insecticides disturbs the environmental system and promotes the appearance of resistant insect species. Therefore, this study investigated the insecticidal effect of some binary monoterpene combinations (1,8 cineole + α-pinene and carvone + R (+)-pulegone) using a mixture design approach. The fumigant toxicity was evaluated against Culex pipiens female adults using glass jars. The results show that the toxicity varies according to the proportions of each compound. Indeed, Mixture 1 (1,8-cineole + α-pinene) displayed a strong toxic effect (51.00 ± 0.86% after 24 h and 100.00 ± 0.70% after 48 h) when the pure compounds were tested at 0.25/0.75 proportions of 1,8-cineole and α-pinene, respectively. Nevertheless, the equal proportion (0.5/0.5) of carvone and R (+)-pulegone in Mixture 2 exhibited a toxic effect of 54.35 ± 0.75% after 24 h and 89.96 ± 0.14% after 48 h, respectively. For Mixture 1, the maximum area of mortality that the proposed model indicated was obtained between 0/1 and 0.25/0.75, while the maximum area of mortality in the case of Mixture 2 was obtained between 0.25/0.75 and 0.75/0.25. Moreover, the maximum possible values of mortality that could be achieved by the validated model were found to be 51.44% (after 24 h) and 100.24% (after 48 h) for Mixture 1 and 54.67% (after 24 h) and 89.99% (after 48 h) for Mixture 2. It can be said that all purev molecules tested through the binary mixtures acted together, which enhanced the insecticide’s effectiveness. These findings are very promising, as the chemical insecticide (deltamethrin) killed only 19.29 ± 0.01% and 34.05 ± 1.01% of the female adults after 24 h and 48 h, respectively. Thus, the findings of our research could help with the development of botanical insecticides that might contribute to management programs for controlling vectors of important diseases. 相似文献
44.
Farah Diab Hawraa Zbeeb Francesca Baldini Piero Portincasa Mohamad Khalil Laura Vergani 《Molecules (Basel, Switzerland)》2022,27(15)
Numerous plants, plant extracts, and plant-derived compounds are being explored for their beneficial effects against overweight and liver diseases. Obesity is associated with the increased prevalence of non-alcoholic fatty liver disease (NAFLD), becoming the most common liver disease in Western countries. Obesity and NAFLD are closely associated with many other metabolic alternations such as insulin resistance, diabetes mellitus, and cardiovascular diseases. Many herbs of the Lamiaceae family are widely employed as food and spices in the Mediterranean area, but also in folk medicine, and their use for the management of metabolic disorders is well documented. Hereby, we summarized the scientific results of the medicinal and nutraceutical potential of plants from the Lamiaceae family for prevention and mitigation of overweight and fatty liver. The evidence indicates that Lamiaceae plants may be a cost-effective source of nutraceuticals and/or phytochemicals to be used in the management of metabolic-related conditions such as obesity and NAFLD. PubMed, Google Scholar, Scopus, and SciFinder were accessed to collect data on traditional medicinal plants, compounds derived from plants, their reported anti-obesity mechanisms, and therapeutic targets. 相似文献
45.
Dr. Farah Benyettou Dr. Anjana Ramdas Nair Yaereen Dho Dr. Thirumurugan Prakasam Dr. Renu Pasricha Jamie Whelan Prof. Hassan Traboulsi Javed Mazher Prof. Kirsten C. Sadler Prof. Ali Trabolsi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(23):5270-5279
Triphenylphosphine (TPP) surface-functionalized and F-108 Pluronic-stabilized gold nanoparticles (F-108@TPP-AuNPs) have been synthesized through a one-step approach, leading to well-defined (9.6±1.6 nm) and water-soluble nanoparticles by microwave heating an aqueous solution of TPP-AuICl in the presence of a Pluronic polymer under basic conditions. TPP release was negligible under physiological conditions, but enhanced significantly at an acidic pH (5.4) mimicking that of a cancer cell. Laser irradiation (532 nm) raised the temperature of an aqueous solution of F-108@TPP-AuNPs to 51.7 °C within 5 min, confirming efficient light-to-heat conversion capabilities without significant photodegradation. TEM confirmed intracellular localization of F-108@TPP-AuNPs in the cytosol, endosomes and lysosomes of HeLa cells. F-108@TPP-AuNPs were well tolerated by HeLa cells and zebrafish embryos at ambient temperatures and became toxic upon heat activation, suggesting synergistic interactions between heat and cytotoxic action by TPP. 相似文献
46.
Majumder Ratan Kumar Das Sudeb Chandra Rasul Md. Golam Khalil Mohammad Ibrahim Dina Nafisa Tamannaya Kabir Mohammad Zafrul Deeba Farah Rajib Mohammad 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):265-277
Journal of Radioanalytical and Nuclear Chemistry - The study investigates the measurement of radon concentration in soils and rocks as a natural tracer for exploring uranium mineralization, first... 相似文献
47.
Maurizio Carotenuto Liberata Guadagno Pio Iannelli Emo Chiellini Abdiaziz Ali Farah Giancarlo Galli 《Journal of Polymer Science.Polymer Physics》1995,33(7):1097-1105
The polymorphic behavior of a polyester consisting of an aromatic triad mesogen and a flexible spacer has been investigated. The effect of thermal and mechanical treatment on the appearance of two crystalline phases stable at room temperature is discussed. The molecular packing (triclinic cell, space group P1 ) and the morphological parameters of the crystalline phase stabilized by drawing process are evaluated and refined. The whole-pattern method, based on the analysis of the whole x-ray diffraction pattern from fiber samples of polymer, has been employed. The molecular packing resembles very much that of polyethylene terephthalate. ©1995 John Wiley & Sons, Inc. 相似文献
48.
Ilijas Farah 《Proceedings of the American Mathematical Society》1996,124(9):2845-2852
We prove that there is a family of partial functions is a tower in such that every surjection is associated to a cohomologically different Hausdorff gap (see Talayco). This improves a result of Talayco.
49.
Abdikani Omar Farah Ryan Archibald Morgan J. Rodriguez Antonio Moreno Blaise Dondji Timothy K. Beng 《Tetrahedron letters》2018,59(38):3495-3498
A flexible and cost-effective method for the highly functional group-compatible and site-selective cross-coupling of readily affordable α-chloro-β-formyltetrahydropyridines has been developed, under nickel or cobalt catalysis, leading to the rapid synthesis of 2,3,5,6-tetrasubstituted dehydropiperidines bearing α-amino allylic stereocenters. Cobalt-catalyzed reductive cross-coupling of chloro enaminals with electronically-diverse bromostyrenes as coupling partners proceeds in good yields and with high E/Z selectivity to afford Diels-Alder-suitable cross-conjugated 1,3-dienes. 相似文献
50.
Deeba Farah Rahman Syed Hafizur Kabir Mohammad Zafrul Dina Nafisa Tamannaya 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):817-826
Journal of Radioanalytical and Nuclear Chemistry - On-site 222Rn concentration at three different soil depths was measured at the south-eastern coastal area of Bangladesh to evaluate the annual... 相似文献