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排序方式: 共有195条查询结果,搜索用时 15 毫秒
91.
Bennett JV Mitchell RE Shepherd MR Besson D Pedlar TK Cronin-Hennessy D Gao KY Hietala J Kubota Y Klein T Lang BW Poling R Scott AW Zweber P Dobbs S Metreveli Z Seth KK Tan BJ Tomaradze A Libby J Martin L Powell A Wilkinson G Ecklund KM Love W Savinov V Mendez H Ge JY Miller DH Shipsey IP Xin B Adams GS Hu D Moziak B Napolitano J He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Artuso M Blusk S Khalil S Li J Mountain R Nisar S Randrianarivony K Sultana N Skwarnicki T Stone S Wang JC 《Physical review letters》2008,101(15):151801
Using a total of 2.74 x 10(7) decays of the psi(2S) collected with the CLEO-c detector, we present a study of chi(cJ)-->gammaV, where V=rho(0), omega, phi. The transitions chi(c1)-->gammarho(0 and chi(c1)-->gammaomega are observed with B(chi(c1)-->gammarho(0))=(2.43+/-0.19+/-0.22) x 10(-4) and B(chi(c1)-->gammaomega)=(8.3+/-1.5+/-1.2) x 10(-5). In the chi(c1)-->gammarho(0) transition, the final state meson is dominantly longitudinally polarized. Upper limits on the branching fractions of other chi(cJ) states to light vector mesons are presented. 相似文献
92.
Grigor L. Georgiev Taslema Sultana Ronald J. Baird Golam Newaz Rahul Patwa 《Applied Surface Science》2008,254(22):7173-7177
KaptonFN film consists of a polyimide core that has been laminated with FEP fluoropolymer outer layers. This composite material's resistance to most chemical solvents, heat sealability and low moisture uptake make KaptonFN attractive as a packaging material for electronics and implantable devices. KaptonFN/Ti micro-joints were fabricated by using focused infrared laser irradiation. The micro-joints were mechanically debonded, and the KaptonFN/Ti interfaces were studied by using X-ray photoelectron spectroscopy (XPS). The locus of failure of the joints was found to be in the FEP layer near the interface with the Ti. The XPS results give evidence for the formation of TiF bond in the interfacial region. 相似文献
93.
Kiran Aftab Kalsoom Akhtar Razia Noreen Faiza Nazir Umme Kalsoom 《Chemistry Central journal》2017,11(1):133
The present investigation aimed to study and compare the efficiency of non-viable fungal isolates to remove divalent lead (Pb(II)) from aqueous streams. The selected fungal isolates showed identity with Aspergillus caespitosus, Aureobasidium sp. RBSS-303 and Aspergillus flavus HF5 as confirmed using gene sequencing of ITS regions of the ribosomal DNA (rDNA). The obtained equilibrium data for Pb(II) biosorption of A. caespitosus fitted better to Langmuir isotherm with maximum sorption capacity of 351.0 mg/g and A. sp. RBSS-303 and A. flavus HF5 showed good fit to Freundlich isotherm with maximum sorption capacity of 271.5 and 346.3 mg/g respectively. The values of thermodynamic factors ascertained the nature of adsorption process is endothermic with A. caespitosus and A. flavus HF5 but exothermic with A. sp. RBSS-303. The experimental data for Pb(II) biosorption fits very well to pseudo second order kinetic model. With HCl the maximum 85.5, 75.3, 73.7% recovery of Pb(II) was obtained from A. caespitosus, A. sp. RBSS-303 and A. flavus HF5, respectively. The observed percentage loss in sorption capacity of Pb(II) was 3.9% by A. flavus HF5, 12.2% by A. caespitosus and 26.6% by A. sp. RBSS-303 after five cyclic studies of sorption and desorption. Results from the study confirmed the efficiency order of A. caespitosus > A. flavus HF5 > A. sp. RBSS-303 to remove and recover Pb(II) from aqueous solution. Finally, the fungal biosorbents can be used as soil conditioning agent after compositing into valuables fungal protein. 相似文献
94.
Kalita Amlan Jyoti Sahu Prem Prakash Borah Ritam Raj Rohman Shahnaz Sultana Kashyap Chayanika Ullah Sabnam Swabaka Baruah Indrani Mazumder Lakhya Jyoti Konwar Dimpul Guha Ankur Kanti 《Structural chemistry》2021,32(6):2313-2318
Structural Chemistry - Sandwich complexes find their interests among the chemists after the breakthrough discovery of ferrocene. Since then, a number of sandwich and half-sandwich complexes were... 相似文献
95.
96.
Juveriya Farooq Rokeya Sultana Tahreen Taj Syed Mohammed Basheeruddin Asdaq Abdulkhaliq J. Alsalman Mohammed Al Mohaini Maitham A. Al Hawaj Mehnaz Kamal Saad Alghamdi Mohd. Imran Haleema Shahin Ruheena Tabassum 《Molecules (Basel, Switzerland)》2022,27(1)
The drugs used to treat cancer not only kill fast-growing cancer cells, but also kill or slow the growth of healthy cells, causing systemic toxicities that lead to altered functioning of normal cells. Most chemotherapeutic agents have serious toxicities associated with their use, necessitating extreme caution and attention. There is a growing interest in herbal remedies because of their pharmacological activities, minimal side effects, and low cost. Thymoquinone, a major component of the volatile oil of Nigella sativa Linn, also known as black cumin or black seeds, is commonly used in Middle Eastern countries as a condiment. It is also utilized for medicinal purposes and possesses antidiabetic, anti-cancer, anti-inflammatory, hepatoprotective, anti-microbial, immunomodulatory, and antioxidant properties. This review attempts to compile the published literature demonstrating thymoquinone’s protective effect against chemotherapeutic drug-induced toxicities. 相似文献
97.
Md Rashedul Islam Md Abdul Awal Ahmed Khames Mohammad A. S. Abourehab Abdus Samad Walid M. I. Hassan Rahat Alam Osman I. Osman Suza Mohammad Nur Mohammad Habibur Rahman Molla Abdulrasheed O. Abdulrahman Sultana Rajia Foysal Ahammad Md Nazmul Hasan Ishtiaq Qadri Bonglee Kim 《Molecules (Basel, Switzerland)》2022,27(7)
98.
Sultana Ferdous Marios A. Ioannidis Dale E. Henneke 《Journal of nanoparticle research》2012,14(5):850
The effects of temperature, pH and sodium chloride (NaCl) concentration on the equilibrium and dynamic interfacial tension (IFT) of 4.4-nm gold nanoparticles capped with n-dodecanethiol at hydrocarbon–water interfaces was studied. The pendant drop technique was used to study the adsorption properties of these nanoparticles at the hexane–water and nonane–water interfaces. The physical size of the gold nanoparticles was determined by TEM image analysis. The interfacial properties of mixtures of these nanoparticles, having different sizes and capping agents, were then studied. The addition of NaCl was found to cause a decrease of the equilibrium and dynamic IFT greater than that which accompanies the adsorption of nanoparticles at the interface in the absence of NaCl. Although IFT values for acidic and neutral conditions were found to be similar, a noticeable decrease in the IFT was found for more basic conditions. Increasing the temperature of the system was found to cause an increase in both dynamic and equilibrium IFT values. These findings have implications for the self-assembly of functionalized gold nanoparticles at liquid–liquid interfaces. 相似文献
99.
AbstractIn this paper, the equivalence between multi-valued maps satisfying the Mizoguchi-Takahashi’s uniformly locally contractive condition and multi-valued maps satisfying the Nadler’s uniformly locally contractive condition is obtained on metrically convex space. We have provided examples to illustrate that this equivalence need not be true on any arbitrary metric space. 相似文献
100.
In some recent derivations thermal characters of the inner horizon have been employed; however, the understanding of possible role that may play the inner horizons of black holes in black hole thermodynamics is still somewhat incomplete. Motivated by this problem we investigate Hawking radiation of the Reissner-Nordström-Taub-NUT (RNTN) black hole by considering thermal characters of both the outer and inner horizons. We apply Damour-Ruffini method and the thin film brick wall model to calculate the temperature and the entropy of the inner horizon of the RNTN black hole. The inner horizon admits thermal character with positive temperature and entropy proportional to its area, and it thus may contribute to the total entropy of the black hole in the context of Nernst theorem. Considering conservations of energy and charge and the back-reaction of emitting particles to the spacetime, the emission spectra are obtained for both the inner and outer horizons. The total emission rate is the product of the emission rates of the inner and outer horizons, and it deviates from the purely thermal spectrum and can bring some information out. Thus, the result can be treated as an explanation to the information loss paradox. 相似文献