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排序方式: 共有118条查询结果,搜索用时 18 毫秒
1.
Sajedi Mohammad Mansoori Yagoub Nuri Ayat Fekri Somayeh Esquivel Dolores Navarro M Angeles 《Catalysis Surveys from Asia》2022,26(3):193-210
Catalysis Surveys from Asia - 2-(2-Pyridyl)benzimidazole (PyBzIm) was supported onto magnetic mesoporous silica, Fe3O4@SiO2@SBA-15 via the click chemistry. The supported ligand was treated with... 相似文献
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In this work, we report a comprehensive theoretical investigation of electroactive star shaped pyrrole functionalized triazine monomer with two main goals. First goal of this work is to explore the physical and chemical properties of the monomer, then to investigate correlation between the experimental and the theoretical properties of monomer. The scale factor which is calculated from B3LYP/cc-pVDZ was determined as 0.985 for FT-IR and it is an important and reliable contribution to the literature. It is determined that the most appropriate basis set for this molecule. The other novel objective of this research is to investigate temperature effect on displacement of chlorine atoms in 2,4,6-trichloro-1,3,5-triazine. This method applied for the first time in the literature for triazines is especially crucial to the synthesis of unsymmetrical triazines. 相似文献
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Nuri Choi Gabsik Yang Joo Hyeon Jang Han Chang Kang Yong-Yeon Cho Hye Suk Lee Joo Young Lee 《Molecules (Basel, Switzerland)》2021,26(4)
Gout is a type of inflammatory arthritis caused by the deposition of monosodium uric acid (MSU) crystals in tissues. The etiology of gout is directly linked to the NLRP3 inflammasome, since MSU crystals are NLRP3 inflammasome activators. Therefore, we decided to search for a small-molecule inhibitor of the NLRP3 inflammasome for the prevention of gout inflammation. We found that loganin suppressed MSU crystals-induced caspase-1 (p20) and interleukin (IL)-1β production and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) specks formation in mouse primary macrophages, showing its ability to inhibit the NLRP3 inflammasome. In an air pouch inflammation model, oral administration of loganin to mice prevented MSU crystals-induced production of mature IL-1β and IL-18 in air pouch exudates, resulting in decreased neutrophil recruitment. Furthermore, oral administration of loganin suppressed MSU crystals-induced gout inflammation in a mouse foot gout model, which was accompanied by the inhibition of the NLRP3 inflammasome. Loganin blocked de novo synthesis of mitochondrial DNA in air pouches and foot tissues injected with MSU crystals. Consistently, loganin prevented MSU crystals-induced mitochondrial damage in macrophages, as it increased mitochondrial membrane potential and decreased the amount of mitochondrial reactive oxygen species. These data demonstrate that loganin suppresses NLRP3 inflammasome activation by inhibiting mitochondrial stress. These results suggest a novel pharmacological strategy to prevent gout inflammation by blocking NLRP3 inflammasome activation and mitochondrial dysfunction. 相似文献
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Nuri Yücel 《Heat and Mass Transfer》1994,29(8):471-477
The flow and heat transfer in partially heated and partially cooled cavities were numerically analyzed. Using the control volume approach, a computer program based on SIMPLE algorithm was developed. A square enclosure with variable size heater and cooler on the vertical walls was considered. Computations were carried out to investigate the effects of heater and cooler size on the heat transfer rate. It was observed that for a given cooler size, the mean Nusselt number decreases with increasing heater size. On the other hand, for a given heater size, the mean Nusselt number increases with increasing cooler size. For all Rayleigh numbers considered, the same behavior was observed.
Nomenclature g gravitational acceleration - H height of cavity - k thermal conductivity of fluid - l C cooler size - l H heater size - mean Nusselt number - Nu y local Nusselt number - P pressure - Pr Prandtl number - Ra Rayleigh number (Ra = gH 3(T H –T C)/()) - T temperature - T C temperature of cold surface - T H temperature of hot surface - T R reference temperature (T R = (T C +T H)/2) - u velocity component inx-direction - x horizontal axis - v velocity component iny-direction - y vertical axis Greek symbols thermal diffusivity - thermal expansion coefficient - density of fluid - stream function - kinematic viscosity 相似文献
Natürliche Konvektion in geschlossenen Räumen mit partieller Heizung und Kühlung der Wände
Zusammenfassung Es wurde ein numerisches Modell zur Analyse des Strömungs- und Wärmeübergangsverhaltens in teilweise beheizten und gekühlten Hohlräumen entwickelt und unter Verwendung des Kontrollvolumenprinzips und des Algorithmus SIMPLE als Computer-Programm formuliert. Der Hohlraum ist rechteckig und die variablen Heiz- und Kühlflächen befinden sich auf gegenüberliegenden Vertikalseiten. Hauptziel der Berechnungen war es, den Einfluß der variablen Heiz- und Kühlflächen auf den Wärmeübergang zu ermitteln. Für eine bestimmte Kühlergröße zeigte sich eine Abnahme der gemittelten Nußelt-Zahl mit zunehmender Heizfläche. Andererseits — bei gegebener Heizfläche — stieg die Nußelt-Zahl mit der Kühlfläche an. Dieses Verhalten wurde bei allen untersuchten Rayleighzahlen gefunden.
Nomenclature g gravitational acceleration - H height of cavity - k thermal conductivity of fluid - l C cooler size - l H heater size - mean Nusselt number - Nu y local Nusselt number - P pressure - Pr Prandtl number - Ra Rayleigh number (Ra = gH 3(T H –T C)/()) - T temperature - T C temperature of cold surface - T H temperature of hot surface - T R reference temperature (T R = (T C +T H)/2) - u velocity component inx-direction - x horizontal axis - v velocity component iny-direction - y vertical axis Greek symbols thermal diffusivity - thermal expansion coefficient - density of fluid - stream function - kinematic viscosity 相似文献
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Nuri Akkas 《International Journal of Non》1978,13(3):177-183
The dynamic behavior of a spherical membrane, made of Mooney material and subjected to a uniform inflating step-pressure, is studied. Its phase-planes and nondimensional radius versus time curves are plotted for different values of the material constants. The conditions for dynamic snapout instability are discussed. The relations between the static behavior of the membrane and the dynamic instability are pointed out. 相似文献
8.
Constrained‐Geometry Bisphosphazides Derived from 1,8‐Diazidonaphthalene: Synthesis,Spectroscopic Characteristics,Structural Features,and Theoretical Investigations 下载免费PDF全文
Julius F. Kögel Nuri C. Abacılar Felicia Weber Dr. Benjamin Oelkers Dr. Klaus Harms Dr. Borislav Kovačević Prof. Dr. Jörg Sundermeyer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(20):5994-6009
Investigations on the Staudinger reaction between 1,8‐diazidonaphthalene and phosphorous(III) building blocks, a key step in the synthesis of superbasic bisphosphazene proton sponges, yielded a set of bisphosphazides with a constrained geometry 1,8‐disubstituted naphthalene backbone. This compound class has attracted our interest not only due to their surprisingly high stability, but in particular because of their theoretically predicted basicity in the range of their bisphosphazene analogues that can be referred to the constrained geometry interaction of two highly basic nitrogen atoms. Eleven new bisphosphazides bearing simple P‐amino groups as well as P‐guanidino substituents, azaphosphatrane moieties, P2 building blocks, or chiral P‐amino substituents derived from L ‐proline are presented. They were studied concerning their spectroscopic properties and partly also their chromophoric and structural features. In the case of the pyrrolidino‐substituted TPPN(2N2) (TPPN=1,8‐bis(trispyrrolidinophosphazenyl)naphthalene), the stepwise nitrogen elimination is investigated theoretically and experimentally, which led to the isolation and structural characterization of TPPN(1N2) bearing a phosphazide and a phosphazene functionality in one molecule. Attempts to protonate the obtained bisphosphazides and to prove the computationally predicted pKBH+ values through NMR titration reactions resulted in their decay, which again was rationalized by theoretical calculations. Altogether we present the so far most extensive spectroscopic, structural and theoretical investigation of constrained geometry bisphosphazides and their Brønsted and Lewis basic properties. 相似文献
9.
H. Ahmad K. Kumar M. A. Rahman M. M. Rahman M. A. J. Miah H. Minami M. A. Nuri 《先进技术聚合物》2013,24(8):740-746
Considering the application potentials of organic materials possessing both conducting and ferromagnetic functions in various electronic devices, an attempt was made to prepare conducting polyaniline (PANI) layered magnetic nano composite polymer particles. Two routes were used to modify magnetic Fe3O4 core particles. In one route, seeded emulsion polymerization of methyl methacrylate (MMA) was carried out in presence of nano‐sized Fe3O4 core particles. In another route, cross‐linker ethyleneglycol dimethacrylate (EGDM) was used in addition to MMA. The modified composite particles were named as Fe3O4/PMMA and Fe3O4/P(MMA‐EGDM), respectively. Finally, seeded chemical oxidative polymerization of aniline was carried out in the presence of Fe3O4/PMMA and Fe3O4/P(MMA‐EGDM) composite seed particles to obtain Fe3O4/PMMA/PANI and Fe3O4/P(MMA‐EGDM)/PANI composite polymer particles. The modification of Fe3O4 core particles was confirmed by electron micrographs, FTIR, UV–visible spectra, X‐ray photoelectron spectra, X‐ray diffraction pattern and thermogravimetric analyses. A comparative study showed that crosslinking of intermediate shell improved the magnetic susceptibility and electrical conductivity of PANI layered magnetic nano composite particles. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
10.
Fatima Dayton J. Vogel Yulun Han Talgat M. Inerbaev Nuri Oncel 《Molecular physics》2019,117(17):2293-2302
ABSTRACTIn this research, ground-state electronic structure and optical properties along with photoinduced electron dynamics of Si nanowires oriented in various directions are reviewed. These nanowires are significant functional units of future nano-electronic devices. All observables are computed for a distribution of wave vectors at ambient temperature. Optical properties are computed under the approximation of momentum conservation. The total absorption is composed of partial contributions from fixed values of momentum. The on-the-fly non-adiabatic couplings obtained along the ab initio molecular dynamics nuclear trajectories are used as parameters for Redfield density matrix equation of motion. The main outcomes of this study are transition energies, light absorption spectra, electron and hole relaxation rates, and electron transport properties. The results of these calculations would contribute to the understanding of the mechanism of electron transfer process on the Si nanowires for optoelectronic applications. 相似文献