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91.
Yundong Qi Charles Musante Kei May Lau Lesley Smith Rajesh Odedra Ravi Kanjolia 《Journal of Electronic Materials》2001,30(11):1382-1386
Bis(cyclopentadienyl)magnesium (Cp2Mg) is a common source for p-type doping in GaN and AlInGaP materials. It is a white crystalline solid with very low vapor
pressure, leading to transport problems similar to solid trimethyindium (TMI). Some of these problems can be alleviated by
a newly developed source-solution magnesocene, Cp2Mg, dissolved in a solvent that is essentially nonvolatile. In this paper, we report the growth and comparative results of
Mg-doped GaN grown by OMVPE using solid and solution Cp2Mg. Using both sources, we optimized parameters to obtain high-quality GaN growth with hole concentrations up to 1 1018/cm3. 相似文献
92.
Xabier Rodríguez-Martínez Paula Hartnagel Sergi Riera-Galindo Gulzada Beket Thomas Österberg Feng Gao Thomas Kirchartz Olle Inganäs 《Advanced functional materials》2023,33(27):2301192
Non-fullerene acceptors have recently revolutionized indoor organic photovoltaics (OPVs) with power conversion efficiencies exceeding 30% in laboratory scale. Nevertheless, transferring their superior performance to larger-scale prototyping, i.e., air-processing via roll-to-roll compatible techniques, still shows severe challenges. Herein, the industrial potential of the PM6:IO4Cl blend, which is one of the most successful indoor OPV photoactive layers (PALs), is thoroughly investigated. The corresponding thick and semitransparent laminated devices are fabricated entirely in air, by blade and slot-die coating. Their current–voltage (J–V) characteristics show anomalous features depending on the illumination side, with the cathode side generally outperforming the anode counterpart. Electrical and optical modeling reveal that a plausible cause of such a phenomenon is a dead layer that forms at the PAL/anode contact interface that does not contribute to the photocurrent. Said layer becomes undetectable when the PALs are made thin enough (<35 nm each) leading to symmetric J–V curves and improved light utilization efficiency. By screening the photovoltaic performance of multiple donor:acceptor blends, certain all-polymer and polymer:fullerene PALs are identified as adequately symmetric candidates for thick device up-scaling. Finally, ternary blends based on PM6:IO4Cl:fullerene may constitute a viable route to mitigate the electrical asymmetry detected on conventional binary blends. 相似文献
93.
94.
舰空导弹超视距拦截制导律设计与指令解算 总被引:2,自引:0,他引:2
针对舰舰协同制导舰空导弹超视距拦截低空飞行目标问题,在初制导段,设计了一种指数型制导律,保证导弹由发射姿态平滑快速地转至装定角;在中末制导段,应用最优控制理论,设计了对目标机动和视线角速率量测噪声具有强鲁棒性的最优制导律;考虑地球曲率,以经纬度位置为基准,通过一系列坐标变换,将目标信息变换到发射坐标系下,建立了制导律所需各种信号指令的解算模型.仿真结果验证了协同制导指令解算模型的正确性和制导律的可行性与鲁棒性. 相似文献
95.
Lithium Phenolate Complexes with a Pyridine‐Containing Polymer for Solution‐Processable Electron Injection Layers in PLEDs 下载免费PDF全文
Takayuki Chiba Yong‐Jin Pu Shogo Takahashi Hisahiro Sasabe Junji Kido 《Advanced functional materials》2014,24(38):6038-6045
A series of (vinylphenyl)pyridine‐based polymer binders, PVPh2Py, PVPh3Py, and PVPh4Py, are designed and synthesized and it is found that mixtures of Liq and the polymers exhibit superior electron injection characteristics as ultrathin (1.6 nm) electron injection layer (EIL) films. They are comparable to those of EILs composed only of Liq. The addition of the polymers does not deteriorate the performance of Liq EILs. Additionally, when the EIL thickness is increased from 1.6 nm to 16 nm, the driving voltages increase and the external quantum efficiencies decrease. The increase in the voltage and decrease in the EQE are suppressed in the device with mixed EILs compared to those observed for the device composed of 100 wt% Liq. Furthermore, the position of the nitrogen in the pyridine ring is considered to influence the electron transport properties of the EILs. The mixing PVPh4Py with Liq improves the driving voltage of the fabricated devices, even with a thick mixed EIL. This reduced dependence of the performance of EILs on their thickness will be advantageous for the coating of large areas using solution processes. 相似文献
96.
利用直接对称方法得到了广义KdV-Zakharov-Kuznetsev方程(简写为mKdV-ZK)的对称约化、精确解,其中包括椭圆函数解,幂级数解,艾米儿函数解等. 利用得到的对称,求出了该方程的守恒律. 相似文献
97.
铝合金化学镀镍工艺研究与应用 总被引:6,自引:0,他引:6
报道一种在铝合金元件上实施化学镀镍的工艺方法。该方法包括在改进的锌酸 溶液中经二闪浸锌处理后,以碱性化学镀镍作底层,然后进行酸性化学镀镍,能在铝合金(LY12cz、LD31等)表面获得光亮的、具有优异附着力和良好的防腐蚀性能及其综合物理、化学特性的化学镀镍(Ni-P)层。 相似文献
98.
在分析现行移动通信网和固定电话网用户编号方案的特点及存在问题的基础上,建议在第三代移动通信网中采用长途区号 3G用户号码的编号方案。 相似文献
99.
级联拉曼激光器的二阶近似解 总被引:1,自引:0,他引:1
利用非线性方法可以得到级联掺磷拉曼光纤激光器的二阶近似解.将描述抽运光和斯托克斯(Stokes)光沿光纤分布的微分方程组简化成代数方程组,在此基础上对抽运光采用二阶非线性近似得到了不同输入抽运功率情况下的近似解,并求出了在二阶非线性近似下的一级Stokes光和二级Stokes光的阈值表达式.利用得到的二阶近似解同一般的数值解法作比较,结果表明两者吻合得很好.一方面,对于双波长输出的级联掺磷拉曼光纤激光器,二阶方法比线性方法更加精确,更接近于一般的数值解;另一方面,该方法有效提高了数值运算速度,优于一般的数值方法. 相似文献
100.
Recharge to the aquifer leads to the growth of a groundwater mound. Therefore, for the proper management of an aquifer system, an accurate prediction of the spatio-temporal variation of the water table is very essential. In this paper, a problem of groundwater mound formation in response to a transient recharge from a rectangular area is investigated. An approximate analytical solution has been developed to predict the transient evolution of the water table. Application of the solution and its sensitivity to the variation of the recharge rate have been illustrated with the help of a numerical example.Notations
a =
Kh/e [L2/T]
-
A =
aquifer's extent in the x-direction [L]
-
B =
aquifer's extent in the y-direction [L]
-
e =
effective porosity
-
h =
variable water table height [L]
-
h
0=
initial water table height [L]
-
h =
weighted mean of the depth of saturation [L]
-
K =
hydraulic conductivity [L]
-
m, n =
integers
-
P =
constant rate of recharge [L/T]
-
P
1+P0=
initial rate of transient recharge [L/T]
-
P
1=
final rate of transient recharge [L/T]
-
s =
h
2–h
0
2
[L2]
-
t =
time of observation [T]
-
x,y =
space coordinates
-
x
2–x1=
length of recharge area in x-direction [L]
-
y
2–y1=
width of recharge area in y-direction [L]
-
z =
decay constant [T-1] 相似文献