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71.
We report the design and fabrication of a novel and fully integrated polymer-based centrifugal microfluidic disc for rapid automatic allergens detection. All essential steps for a single test including flow valving, sequencing, mixing, separation, extraction, and sedimentation for final detection are automatically conducted within 30 min on a centrifugal microfluidic disc. Our design features a siphon-based valving and analyte extraction structure where the released analyte is separated and subsequently extracted by a siphon valve into the detection chamber. Incorporating the siphon valve and a series of capillary valves, we realize automated detection of allergic reaction on a centrifugal microfluidic disc.  相似文献   
72.
Bulk工艺气体微网探测器的研究   总被引:1,自引:0,他引:1  
In this paper, we present a study of a micromegas detector prototype built with bulk technology. Following a short discussion of the micromegas detector's structure and working mechanism, the bulk fabrication process is described, and some testing results of the prototype are presented.  相似文献   
73.
王宁  张帅  刘玉敏 《运筹与管理》2020,29(6):210-219
为解决多工序制造过程关键质量特性识别中存在的质量特性间具有多重相关性以及数据高维度, 小样本等问题,本文采用主成分回归改进Adaptive Lasso方法并融合状态空间思想和Bootstrap方法实现多工序过程关键质量特性识别。首先引入状态空间思想构建多工序过程关键质量特性识别模型,然后利用Bootstrap方法重构样本,扩大样本量;进而采用改进Adaptive Lasso方法识别关键质量特性,并通过仿真验证改进Adaptive Lasso方法与Lasso,Adaptive Lasso和岭回归方法在质量特性间不同相关度下识别的有效性;最后通过实例说明改进Adaptive Lasso的具体应用过程,仿真及实例结果显示,改进Adaptive Lasso方法对多工序过程有良好的关键质量特性识别能力,特别当质量特性间有较强相关性时显著优于其它两种方法。  相似文献   
74.
制造企业服务化是我国实现制造强国的必经之路,本文以“中国制造2025”战略为背景,通过借鉴创新扩散和演化博弈理论,对社会系统中参与服务创新的相关主体进行分析,构建政府与企业之间演化博弈模型,结合并改进Bass经典创新扩散模型,探究政府规制行为对企业服务创新行为演化及扩散的影响,利用Matlab对复制动态方程和扩散模型进行数学推导和数值仿真分析。结果表明:当满足政府的社会总收益大于其调控成本和各项补贴总额且企业选择服务创新策略时收益的额外增加额大于其实际投入时,系统才会演化至政府调控且企业采纳服务创新的稳定状态;适当增加政府对企业的调控力度、投入补贴和税收补贴有助于推进服务创新在系统中的扩散,其中税收补贴的感知能力最强,投入补贴最弱;将抑制系数引入Bass创新扩散模型,构建互补型、竞争型和替代型三种服务创新的扩散模式,其中竞争型扩散符合中国现阶段市场规律,替代性扩散将成为未来制造企业的发展趋势。  相似文献   
75.
为了准确测试和评价大口径连续相位板(CPP)元件的远场光强性能,根据激光装置需求建立了351 nm波长下大口径CPP远场光强离线测试系统,开展了330 mm330 mm口径CPP元件测试实验,并与标量衍射计算结果进行对比,分析了系统的测试重复性和测试精度。实测系统远场弥散斑大小为2.9倍衍射极限,可测试最大口径为圆形f600 mm和方形430 mm430 mm。测试系统在焦点2 mm范围内的能量集中度测试重复性优于0.2 %。计算和实验焦斑形貌及分布吻合,实测能量集中度比计算结果小0.85%、焦斑半径大13 m左右,差异由实测系统的时间匀滑作用引起,可通过缩短曝光时间和减小系统像差等措施进一步提高测试精度。  相似文献   
76.
A novel broadband transmission method to determine polymer film thickness during manufacturing is proposed, and a measurement system is developed based on this method. The relationship between broadband optical power and film thickness is deduced according to the Lambert-Beer law. The system is composed of a halogen light and an optical power meter. Results show that the measurement error of this method is approximately 1 μm, and the resolution of the system is below 0.4 μm for polymer films with less than 100-μm thickness.  相似文献   
77.
The detection of low-level light is a key technology in various experimental scientific studies. As a photon detector, the silicon photomultiplier (SiPM) has gradually become an alternative to the photomultiplier tube (PMT) in many applications in high-energy physics, astroparticle physics, and medical imaging because of its high photon detection efficiency (PDE), good resolution for single-photon detection, insensitivity to magnetic field, low operating voltage, compactness, and low cost. However, primarily because of the geometric fill factor, the PDE of most SiPMs is not very high; in particular, for those SiPMs with a high density of micro cells, the effective area is small, and the bandwidth of the light response is narrow. As a building block of the SiPM, the concept of the backside-illuminated avalanche drift detector (ADD) was first proposed by the Max Planck Institute of Germany eight years ago; the ADD is promising to have high PDE over the full energy range of optical photons, even ultraviolet light and X-ray light, and because the avalanche multiplication region is very small, the ADD is beneficial for the fabrication of large-area SiPMs. However, because of difficulties in design and fabrication, no significant progress had been made, and the concept had not yet been verified. In this paper, preliminary results in the design, fabrication, and performance of a backside-illuminated ADD are reported; the difficulties in and limitations to the backside-illuminated ADD are analyzed.  相似文献   
78.
In the integrated circuit manufacturing process, the critical area extraction is a bottleneck to the layout optimization and the integrated circuit yield estimation. In this paper, we study the problem that the missing material defects may result in the open circuit fault. Combining the mathematical morphology theory, we present a new computation model and a novel extraction algorithm for the open critical area based on the net flow-axis. Firstly, we find the net flow-axis for different nets. Then, the net flow-edges based on the net flow-axis are obtained. Finally, we can extract the open critical area by the mathematical morphology. Compared with the existing methods, the nets need not to divide into the horizontal nets and the vertical nets, and the experimental results show that our model and algorithm can accurately extract the size of the open critical area and obtain the location information of the open circuit critical area.  相似文献   
79.
<正>硼酸盐非线性光学晶体材料作为一类重要的光电功能材料,已在航天、能源、工业制造、医学、科研等领域有广泛应用。中国科学院新疆理化技术研究所光电功能材料团队针对卤素硼酸体系,通过调控结构,设计合成了一系列性能优异的含卤素碱金属/碱土金属硼酸盐非线性光学晶体,如Ba4B11O20F(J.Am.Chem.  相似文献   
80.
为提升组建效率,降低组建难度与成本,在分析区域小微企业及其群体特点的基础上,提出由小微企业构建产品制造模块,通过模块的组合,形成大规模客户化制造系统的模块化组建方法.同时,结合对产品制造模块及其构建方式,以及模块选择主要影响因素的分析,研究了基于模块选择系数的制造模块选择策略,为制造系统的模块化组建提供了必要条件.  相似文献   
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