全文获取类型
收费全文 | 173篇 |
免费 | 7篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 46篇 |
金属工艺 | 8篇 |
机械仪表 | 6篇 |
建筑科学 | 4篇 |
能源动力 | 8篇 |
轻工业 | 40篇 |
水利工程 | 3篇 |
石油天然气 | 1篇 |
无线电 | 9篇 |
一般工业技术 | 23篇 |
冶金工业 | 11篇 |
原子能技术 | 1篇 |
自动化技术 | 19篇 |
出版年
2024年 | 2篇 |
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 19篇 |
2020年 | 9篇 |
2019年 | 8篇 |
2018年 | 6篇 |
2017年 | 2篇 |
2016年 | 6篇 |
2015年 | 5篇 |
2014年 | 16篇 |
2013年 | 17篇 |
2012年 | 13篇 |
2011年 | 13篇 |
2010年 | 7篇 |
2009年 | 14篇 |
2008年 | 9篇 |
2007年 | 5篇 |
2006年 | 2篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有180条查询结果,搜索用时 312 毫秒
61.
Şenol Durmuşoğlu İbrahim Uslu Tuncay Tunç Selda Keskin Arda Aytimur Ahmet Akdemir 《Journal of Polymer Research》2011,18(6):1999-2004
Boron doped poly(vinyl) alcohol/ bismuth - lanthanum acetate (PVA/Bi-La) nanofibers were prepared by electrospinning using
PVA as a precursor. The effect of boron doping was investigated in terms of solution properties, morphological changes and
thermal characteristics. The fibers were characterized by FT-IR, XRD, SEM and BET. The addition of boron did not only increase
the thermal stability of the fibers, but also their diameters, which yielded stronger fibers. XRD analyses showed that boron
doping increased the peak intensities and indicated that the boron doping enhanced the crystallite size. Moreover, no shifts
were noticed in diffraction angles for boron doped and undoped samples. Therefore, boron doping did not significantly alter
the lattice spacing. The SEM micrograph of the fibers showed that the addition of boron resulted in the formation of cross
linked bright surfaced fibers. Also, grain diameters of boron doped and undoped nanocrystalline sintered powders were measured
as 170 nm and 120 nm respectively. The BET results show that boron undoped and doped Bi2O3-La2O3 nanocrystalline powder ceramic structures sintered at 800 °C have surface areas of 20.44 m2/g and 12.93 m2/g, respectively. 相似文献
62.
Tuncay Tunç Şemsettin Altındal İlbilge Dökme Habibe Uslu 《Journal of Electronic Materials》2011,40(2):157-164
In this study, the temperature-dependent mean density of interface states (NSS)(N_{\rm SS}) and series resistance (RS)(R_{\rm S}) profiles of Au/PVA (Ni,Zn-doped)/n-Si(111) structures are determined using current–voltage (I−V) and admittance spectroscopy [capacitance–voltage (C–V) and conductance–voltage G/ω–V] methods. The other main electronic parameters such as zero-bias barrier height (FB0)(\Phi_{{\rm B}0}), ideality factor (n), and doping concentration (N
D) are also obtained as a function of temperature. Experimental results show that the values of FB0\Phi_{\rm{B}0}, n, R
S, and N
SS are strongly temperature dependent. The values of FB0\Phi_{\rm{B}0} and R
S increase with increasing temperature, while those of n and N
SS decrease. The C–V plots of Au/PVA (Ni,Zn-doped)/n-Si(111) structures exhibit anomalous peaks in forward bias (depletion region) at each temperature, and peak positions shift
towards negative bias with increasing temperature. The peak value of C has been found to be strongly dependent on N
SS, R
S, and temperature. The experimental data confirm that the values of N
SS, R
S, temperature, and the thickness and composition of the interfacial polymer layer are important factors that influence the
main electrical parameters of the device. 相似文献
63.
Tuncay Tunç ?emsettin Altindal ?brahim Uslu ?lbilge Dökme Habibe Uslu 《Materials Science in Semiconductor Processing》2011,14(2):139-145
Current–voltage (I–V) characteristics of Au/PVA/n-Si (1 1 1) Schottky barrier diodes (SBDs) have been investigated in the temperature range 80–400 K. Here, polyvinyl alcohol (PVA) has been used as interfacial layer between metal and semiconductor layers. The zero-bias barrier height (ΦB0) and ideality factor (n) determined from the forward bias I–V characteristics were found strongly dependent on temperature. The forward bias semi-logarithmic I–V curves for different temperatures have an almost common cross-point at a certain bias voltage. The values of ΦB0 increase with the increasing temperature whereas those of n decrease. Therefore, we have attempted to draw ΦB0 vs. q/2kT plot in order to obtain evidence of a Gaussian distribution (GD) of the barrier heights (BHs). The mean value of BH and standard deviation (σ0) were found to be 0.974 eV and 0.101 V from this plot, respectively. Thus, the slope and intercept of modified vs. q/kT plot give the values of and Richardson constant (A?) as 0.966 eV and 118.75 A/cm2K2, respectively, without using the temperature coefficient of the BH. This value of A* 118.75 A/cm2K2 is very close to the theoretical value of 120 A/cm2K2 for n-type Si. Hence, it has been concluded that the temperature dependence of the forward I–V characteristics of Au/PVA/n-Si (1 1 1) SBDs can be successfully explained on the basis of the Thermionic Emission (TE) theory with a GD of the BHs at Au/n-Si interface. 相似文献
64.
B. Dogan-Topal Dilek Kul Sibel A. Ozkan B. Uslu 《Journal of Applied Electrochemistry》2011,41(11):1253-1260
The electrochemical oxidation of fulvestrant was made on highly boron-doped diamond electrode using differential pulse adsorptive
stripping voltammetry. The highest current intensities were obtained by applying +1.10 V during 150 s for boron-doped diamond
electrode. For boron-doped diamond electrode, linear responses were obtained for the concentrations between 1 × 10−6 and 8 × 10−5 M in standard samples and between 1 × 10−6 and 4 × 10−5 M in serum samples. The repeatability of the method was 0.55 RSD% for differential pulse adsorptive stripping voltammetry.
The analytical values of the method are demonstrated by quantitative determination of fulvestrant in pharmaceutical formulations
and human serum, without the need for separation or complex sample preparation, since there was no interference from the excipients
and endogenous substances. Selectivity, reproducibility, and accuracy of the developed methods were demonstrated by recovery
studies. 相似文献
65.
Ethanol has been considered as an alternative fuel for diesel engines. On the other hand, injection timing is a major parameter that sensitively affects the engine performance and emissions. Therefore, in this study, the influence of advanced injection timing on the engine performance and exhaust emissions of a single cylinder, naturally aspirated, four stroke, direct injection diesel engine has been experimentally investigated when using ethanol‐blended diesel fuel from 0 to 15% with an increment of 5%. The original injection timing of the engine is 27° crank angle (CA) before top dead center (BTDC). The tests were conducted at three different injection timings (27, 30 and 33° CA BTDC) for 30 Nm constant load at 1800 rpm. The experimental results showed that brake‐specific energy consumption (BSEC), brake‐specific fuel consumption (BSFC), NOx and CO2 emissions increased as brake‐thermal efficiency (BTE), smoke, CO and HC emissions decreased with increasing amount of ethanol in the fuel mixture. Comparing the results with those of original injection timing, NOx emissions increased and smoke, HC and CO emissions decreased for all test fuels at the advanced injection timings. For BSEC, BSFC and BTE, advanced injection timings gave negative results for all test conditions. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
66.
M. E. Yakıncı Y. Balcı M. A. Aksan H. İ. Adigüzel A. Gencer 《Journal of Superconductivity and Novel Magnetism》2002,15(6):607-611
Superconducting MgB2 polycrystalline samples have been fabricated under two different conditions in order to determine the effect of MgB4 phase. A series of samples was placed in an α-alumina container closed with a cup and fired under high purity argon gas. The other series of samples was placed in an α-alumina boot without any lid and fired under similar conditions. For the first series of samples, we have found pure MgB2 phase formation and a narrow transition width at 0.4 K. For the second series of samples, significant amount of MgB4 phase were formed and the T zero was decreased to 27 K. For both the group of samples magnetization hysteresis loops obtained at various temperature range and applied field up to 2 T. The best J cmag for the first series of samples was 1.9 × 105 A/cm2 at 10 K and 0 T, and for the second series of samples was 0.7 × 104 A/cm2 at 10 K and 0 T. 相似文献
67.
Laminated Veneer Lumber (LVL) panels made from eucalyptus (Eucalyptus camaldulensis Dehn.) and beech (Fagus orientalis Lipsky.) veneers were tested for physical and mechanical strength properties in this study. Urea formaldehyde (UF) and Polyvinyl acetate (PVA) adhesives were used for eucalyptus LVL panels and UF adhesive for beech LVL panels. The effect of veneer wood species on some physical and mechanical properties was found statistically significant. Also, different glue species caused the differences in strength properties of LVL panels.
Über einige Eigenschaften von Furnierschichtholzplatten hergestellt aus Buchen- und Eukalyptusfurnieren
Zusammenfassung In diesem Beitrag werden einige physikalische und mechanische Eigenschaften von Schichtholzplatten, hergestellt aus Buchen- (Fagus orientalis Lipsky.) und Eukalyptusfurnieren (Eucalyptus camaldulensis Dehn.) untersucht. Für die Herstellung von Schichtholzplatten wurden die Buchenfurniere mit UF und die Eukalyptusfurniere mit UF und PVA verleimt. Die Ergebnisse zeigen, dass sowohl die Art des Bindemittels als auch die Holzart der Furniere die Eigenschaften der Schichtholzplatten signifikant beeinflussen.相似文献
68.
Abacavir (I), a drug used in the treatment of HIV, is electrochemically reduced at the dropping mercury electrode in a four-electron process, similar to structurally related adenine (III) and adenosine triphosphate (IV). To undergo the reduction, the species is protonated in the vicinity of the electrode. The protonations take place on the 6-amino group and on one of the pyrimidine ring nitrogens. The role of covalent hydration of the pyrymidine ring has been interpreted. Best suited as supporting electrolytes for analytical purposes are solutions of 0.1-1.0 M sulfuric, perchloric, or hydrochloric acids. Procedures of analyses of tablets containing I were established and validated, based on peak currents obtained by linear sweep, differential pulse, or square-wave voltammetry with a hanging mercury drop electrode as indicator electrode. The procedure proved to be more sensitive and more reliable than that based on oxidation on a glassy carbon electrode, proposed previously. 相似文献
69.
70.
The efficiency of ozonation on the degradation of oxytetracycline, a veterinary antibiotic, has been investigated in both cow manure and synthetic animal feeding operation wastewater at varying experimental conditions. With a rapid degradation of antibiotic in synthetic wastewater, ozonation improved its biodegradability and eliminated bacterial toxicity caused by oxytetracycline. The degradation rate of oxytetracycline depended on pH and applied ozone dose, but not initial antibiotic concentration in wastewater. In the case of manure treatment, ozonation efficiency in terms of oxytetracycline degradation was negatively affected by moisture and antibiotic content of manure. The degradation rate of oxytetracycline in manure slowed down upon the extension of treatment time since ozone could not react with strongly adsorbed antibiotic on manure. Increase in humic and fulvic acid carbon and mineral nitrogen content was an indicator for the improvement of fertilizing value of manure by ozonation. 相似文献