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991.
张志远  宋辉  李想  许英健  朱昱  王磊 《分析测试学报》2022,41(11):1658-1663
建立了QuEChERS结合超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UPLC-QE-OrbitrapMS)同时测定全血中10种新型合成大麻素的分析方法。全血样本经优化的QuEChERS法提取后,采用HypersilGOLDTMVanquish色谱柱(100mm×2.1mm,1.9μm),以0.1%甲酸水和0.1%甲酸乙腈为流动相进行梯度洗脱分离,在加热电喷雾离子源正离子/平行反应监测(HESI+/PRM)模式下同时进行检测。结果表明,10种目标物质在对应质量浓度范围内呈良好线性,相关系数(r2)均不小于0.9990,检出限(LOD)为0.01~0.05ng/mL,定量下限(LOQ)为0.05~0.20ng/mL,回收率为92.1%~115%,基质效应为86.6%~115%,日内相对标准偏差(RSD)均不大于8.5%,日间RSD均不大于10%。该方法具有操作简便、选择性好,检测灵敏度及回收率高的特点,适用于法庭科学全血样本中合成大麻素的检验鉴定。  相似文献   
992.
    
Metasurfaces have attracted extensive attentions due to their great flexibility in controlling the properties of electromagnetic wave in the past decade. Through engineering the geometry and configuration of building subwavelength structures, all the properties of electromagnetic wave, such as amplitude, phase, polarization, etc., can be fully manipulated at will. However, the existing metasurfaces usually provide fixed functions after the structure has been fabricated, which is unfriendly to the trend of high-integraion and multifunctional nanophotonic devices. Therefore, tunable metasurfaces gradually become a new growth area.The optical response of metasurfaces highly relies on the resonant properties of individual subwavelength structures. In general, the optical resonance of each subwavlength structure is dependent on the geometry size, configuration and refractive index of either building material or the immemdiate environment, leading to several mechanisms to realize tunable metasurfaces, i.e., actively tuning the geometry characteristics of structures or the refractive index of involved materials.At present, there are three design routes for tunable metasurfaces: 1) changing the optical response of the structure by external excitation, such as electric/magnetic/optical excitation, chemical reaction and thermal excitation; 2) using special active materials, such as liquid crystals, phase change materials and functional optical crystals; 3) applying an external force to make the structure deformation, such as Micro-electro-mechanical System (MEMS), flexible tensile materials, etc. These control schemes can make the metasurfaces show flexible dynamic response to incident light. Among various tuning mechanisms, the functionalities of electrically tuning metasurfaces grow as one of the most promising technical routes because it can be readily integrated with mature optoelectric devices and semiconductor manufacturing process.Based on different responses of some special materials to electric fields, the design scheme of electrically tunable metasurfaces can be classified into several groups. The refractive index of some active materials, such as Transparent Conducting Oxide (TCO), graphene, Transition Metal Dichalcogenides (TMDs) and Ⅲ-Ⅴ compound semiconductors, can be electrically tuned by controlling the carrier density. As a result, the amplitude and phase of metasurfaces can be effectively controlled. In particular, by combining with plasmonic resonances or other types of local resonances, the tuning range and rate of amplitude and phase can be further improved. Beam deflection, dynamic focusing, optical switch, etc., have been demonstrated at a wide frequency range by selecting suitable materials. However, the thickness of active layer contributing to the tuning effect is usually very thin, which limits the tuning performance and increases the fabrication challenging.In contrast, tunable metasurfaces based on liquid crystals provide large refractive index range along with the advantages of low loss and low cost. By covering the dielectric subwavelength structures with liquid crystals, light propogation behaviors can be controlled with low external voltages. However, long response time and microscale molecule size are inapplicable to high speed and miniaturized optoelectric devices. In addition, it is still challenging to impove the damage threshold for high power applications.Electro-optic (EO) crystals, such as lithium niobate, have a excellent optical response to external voltage and have been widely used in commericialized optoelectric deivces. By integrating with subwavelength structures, such tuning capability can be further enhanced with the footprint of the related devices several orders of magnitude smaller. With the advent of new materials, such as PMN-PT, EO crystal based optoelectric devices will attract increasing interest.Desipite the refractive index tuning scheme, the geometry or structure configuration can also be manipulated by an external voltage. Various applications based on the combinatioin of MEMS and subwavelength structures have been demonstrated, such as varifocal lens, logical calculation, and Light Detection and Ranging (LiDAR) covering a broad frequency range, which will play a crucial role in photonic devices and nanophotonic chips.In this paper, the main design schemes of electrically tunable metasurfaces in recent years have been reviewed. According to the active materials, electrically tunable metasurfaces can be divided into four groups: electrically controlled carrier excitation, liquid crystal, electro-optic crystal and MEMS. The underlying mechanisms, the developing status, pro and con of various schemes are summarized. Finally, the application prospects of different tuning schemes are discussed and the development trend of this area is forecasted. As the development of design theory, material growth and fabrication technique, we believe that electrically tunable metasurfaces will proliferate rapidly and pave the avenue for miniaturized and integrated multifunctional optoelectric devices.  相似文献   
993.
通过简单的一步反应合成了一种新型含硅氧烷基团的苝二酰亚胺(PDI-TES)荧光传感器.结合小角X射线衍射、紫外-可见吸收光谱、荧光光谱和动态光散射等实验方法,阐明了PDI-TES的晶体结构、自组装行为和检测性能.实验结果表明,PDI-TES具有良好的热稳定性和有序的晶体结构.此外,由于Si—O键的断裂,PDI-TES对氟离子具有较高的选择性和灵敏度,检出限低至1.58×10-6mol/L.这些优良的检测性能和简单、低成本的合成方法,有望使PDI-TES成为一种实用的氟离子检测荧光传感器.  相似文献   
994.
应力发光是某些材料受到机械刺激时产生的发光现象。许多固体材料在压裂过程中会产生应力发光,但这种破坏性发光限制了材料的实际应用。可再生应力发光的发现为应力发光材料创造了解决现实问题的机会,其在结构健康诊断、力驱动的新型光源和显示器件以及生物力学应力传感器等领域展现出广泛的应用前景。本文对近二十年来无机可再生应力发光材料的研究进展进行了梳理和总结,主要介绍无机可再生应力发光材料的分类、表征、机理和应用四个方面,并讨论了未来研究中所面临的机遇和挑战,以期对该类材料的研发及应用提供有意义的启示。  相似文献   
995.
基于金属有机骨架的拓扑三维结构的高比表面积以及金纳米颗粒(AuNPS)的优异电催化活性,金纳米颗粒与金属有机框架的复合材料在电化学传感领域拥有应用潜力。该文成功合成了AuNPs@NU-901复合材料,并采用透射电镜、X射线衍射、红外光谱以及X射线光电子能谱对其进行表征。采用线性扫描伏安法和差分脉冲伏安法研究了复合材料对丁基羟基茴香醚(BHA)电化学氧化反应的催化能力。结果表明,AuNPs@NU-901对BHA的电化学氧化具有较好的催化能力。基于AuNPs@NU-901制备电化学传感器用于BHA的定量检测,BHA的氧化峰电流与其浓度在0.10~50μmol/L范围内呈现良好线性关系,相关系数(r2)为0.9948,检出限(S/N=3)为0.049μmol/L,相对标准偏差(RSD)为3.6%。将该传感器应用于饼干样品中BHA的检测,加标回收率为95.6%~104%,样品检测结果与高效液相色谱法的测定结果吻合。方法的选择性好、灵敏准确,适合于饼干中BHA的检测。  相似文献   
996.
该研究基于暴露生物标记物溯源思路,应用于解决芥子气(SM)临床早期诊断、溯源确证难题。建立了芥子气中毒患者尿液中7种游离代谢产物的两步固相萃取/超高效液相色谱-串联质谱(SPE/UPLC-MS/MS)同时定量方法,检出限为5pg/mL~1ng/mL,定量下限为10pg/mL~5ng/mL;结合前期建立的4种游离碱基加合物的同位素稀释-UPLC-MS/MS定量方法,对1例疑似芥子气中毒人员尿液中可能赋存的生物标记物进行了全筛查分析。尿液中共检出3类10种生物标记物,包括首次报道的游离代谢产物芥子亚砜,可确证患者为芥子气中毒;除硫二甘醇外,标记物含量均在暴露后3~4d达到峰值,随后降低,至7d仍可检出,其中谷胱甘肽加合物的β裂解产物含量相对较高,可作为芥子气中毒早期诊断与疗效评估的重要指标。  相似文献   
997.
该文基于酶辅助靶标循环信号放大策略构建了用于黄曲霉毒素B1(AFB1)高灵敏检测的化学发光适体传感器。以G-四链体/氯化血红素DNA酶为信号分子设计了免标记的适体探针H1-S1和发夹探针H2。适体探针结合目标AFB1,在核酸外切酶I辅助下,触发靶标循环反应产生发夹H1。发夹H1与H2杂交,释放出完整的G四链体序列,并进一步与氯化血红素结合形成G-四链体/氯化血红素DNA酶。DNA酶通过催化氧化鲁米诺-H2O2化学发光体系产生化学发光信号,实现AFB1的放大检测。在最优实验条件下,化学发光强度与AFB1质量浓度的对数在0.001~100ng/mL范围内呈良好的线性关系,相关系数(r2)为0.9955,检出限为0.93pg/mL,回收率为93.7%~107%。该适体传感器操作简单、灵敏度高、特异性好,在黄曲霉毒素污染检测方面具有良好的应用前景。  相似文献   
998.
Three new metal-organic complexes, namely [Zn(POA)2(H2O)2](1), [Zn(POA)2(H2O)2]·2H2O(2) and [Zn(POA)2]n(3), have been synthesized by organic ligand 2-carboxylic acid-4-nitropyridine-1-oxide(POA) and zinc(Ⅱ) ions. The structures of complexes 1~3 are characterized by single-crystal X-ray analysis, XRD powder diffraction analysis, infrared spectroscopy and thermal stability analysis method. Complex 1 belongs to monoclinic system, space group C2/c with a = 22.8215(15), b = 7.5613(16), c = 10.048(3) ?, β = 109.47°, V = 1634.7(6) ?~3, Z = 4, F(000) = 944, Dc = 1.900 g/cm^3, C(12)H(10)N4O(12)Zn, Mr = 467.61 and μ = 1.584 mm-1. The whole molecule presents \"V\" shape. Complex 2 is a centrosymmetric structure in triclinic system with space group P1: a = 7.4728(5), b = 7.6825(6), c = 8.5184(6) ?, α = 65.975(2), β = 79.87(2), γ = 89.855(2)°, V = 4384.1(5) ?~3, Z = 1, F(000) = 256, Dc = 1.908 g/cm^3, C(12)H(14)N4O(14)Zn, Mr = 503.64 and μ = 1.492 mm-1. Complex 3 is a one-dimensional chain structure belonging to monoclinic system and space group P21/c with a = 4.9456(6), b = 12.5322(14), c = 11.2514(13) ?, β = 97.313(11)°, V = 6916.8(14) ?~3, Z = 2, F(000) = 432, Dc = 2.072 g/cm^3, C(12)H6N4O(10)Zn, Mr = 431.58, and μ = 1.852 mm-1. In three complexes, six oxygen atoms from the surrounding coordination atoms form a ZnO6 distorted octahedral coordination geometry around the zinc ions. Meanwhile, fluorescent properties of the three complexes were investigated at room temperature. The fluorescence spectroscopic analysis demonstrated that the ligand POA shows red-shift after coordinating with the zinc(Ⅱ) ions.  相似文献   
999.
该文发展了一种无皂液乳化技术制备萘乙酸(NAA)磁性分子印迹聚合物(mMIPs)多孔微球的方法。以甲基丙烯酸-苯乙烯聚合物前驱体为功能单体,NAA为模板分子,与Fe3O4磁流体和引发剂偶氮二异丁腈混合,采用“一锅法”快速制得NAA-mMIPs微球。采用扫描电镜、透射电镜、红外光谱仪等对微球进行了表征,结果表明该微球粒径约80μm,且具有多孔结构,孔径在1~10μm之间。等温吸附实验和Scatchard分析结果表明,该mMIPs微球对NAA同时存在高和低两种亲和位点,其解离常数和最大表观结合量分别为161.30µg·mL-1、29.35mg·g-1和-128.20µg·mL-1、-19.50mg·g-1。吸附动力学实验表明,该mMIPs可在120min内对NAA达到吸附平衡,其吸附行为符合伪二级动力学模型,决速步为化学吸附。对实际番茄汁样品进行3水平的加标回收实验,回收率为78.7%~89.2%,相对标准偏差(RSD)小于3.9%(n=3)。当NAA含量低至0.005µg·mL-1时,平均回收率仍可高达80.3%(RSD<5.0%),该浓度远远低于国标或欧盟标准中对NAA残留量的规定(100、60μg·kg-1)。实验结果表明所制备的mMIPs对NAA表现出高选择性和特异性,并且具有合成简单、操作简便等特点,可有效消除农产品复杂基质对NAA检测的影响,显著提高了鉴定的准确性和可靠性。  相似文献   
1000.
该研究优化了医用口罩样本中16种有机磷酸酯(OPEs)的萃取和净化前处理过程,建立了超高效液相色谱-串联质谱(UPLC-MS/MS)测定方法。样本经甲醇超声萃取后,采用ENVI-18固相萃取小柱净化,最终使用AcquityUPLCBEHC18色谱柱以5mmol/L乙酸铵缓冲溶液-甲醇为流动相进行分离,采用UPLC-MS/MS测定,内标法定量。结果表明,16种OPEs在0.1~50µg/L质量浓度范围内呈良好的线性关系(r>0.995),方法检出限为0.00460~1.03ng/dm2,定量下限为0.0152~3.43ng/dm2,加标回收率为68.8%~140%,相对标准偏差为0.70%~18%。采用所建立的方法对42个医用口罩中16种OPEs进行测定,其总浓度为6.60~2387ng/dm2,其中12种OPEs的检出率高于50%,表明这些OPEs在医用口罩中普遍存在。磷酸三苯酯(TPHP)和磷酸三(1-氯-2-丙基)酯(TCIPP)为主要的OPEs,浓度分别为0.131~2274ng/dm2和0.370~79.8ng/dm2。整体上OPEs的浓度均较低,推测口罩样本中的OPEs可能是生产和包装过程中受空气或塑料包装污染所致。  相似文献   
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