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排序方式: 共有110条查询结果,搜索用时 15 毫秒
41.
We propose a potentially practical scheme for implementing an
n-qubit Toffoli gate by elaborately controlling the transport of
ultracold ions through stationary laser beams. Conditioned on the
uniform ionic transport velocity, the n-qubit Toffoli gate can be realized
with high fidelity and high successful probability under current experimental
conditions, which depends on a single resonant interaction with n trapped
ions and has constant implementation time with the increase of qubits.
We show that the increase of the ion number can improve the fidelity and
the successful probability of the Toffoli gate. 相似文献
42.
Li Xue-Mei Mi Qi-Li Gao Qian Li Jing Song Chun-Man Zeng Wan-Li Xiang Hai-Ying Liu Xin Chen Jian-Hua Zhang Cheng-Ming Yang Guang-Yu Hu Qiu-Fen Chen Zhang-Yu 《Chemistry of Natural Compounds》2021,57(2):293-296
Chemistry of Natural Compounds - Two new naphthalene derivatives, 1-(3-hydroxy-1-(hydroxymethyl)-2-methoxy-6-methylnaphthalen-7-yl) propan-2-one (1) and... 相似文献
43.
Five types of new pyridine-based azo compounds, namely, 4-(4′-pyridylazo)-4′‘-alkoxybenzoates or 4-(4′-pyridylazo)-4′’-substituted benzoates with straight or branch terminal were prepared as hydrogen bond (H-bond) acceptors to build mesogens. After self-assembled with different carboxylic acids, the resulted H-bond complexes were confirmed for the stability of H bond by fourier transform infrared spectroscopy (FTIR) spectroscopy, and investigated for the mesophase behaviour by differential scanning calorimetry and polarised optical microscopy. The influence of terminal chains in azo accepter or acid donor and the structure of acid donors on the mesogenic behaviour were discussed in detail. 相似文献
44.
采用高温固相法制备了SrZn2(PO4)2:Sn2+(SZ2P:Sn2+), SrZn2(PO4)2:Mn2+(SZ2P:Mn2+), SrZn2 (PO4)2:Sn2+, Mn2+(SZ2P:Sn2+, Mn2+) 荧光粉. 通过X射线衍射、激发和发射光谱详细研究了荧光粉的物相和发光性质. 在SrZn2(PO4)2 基质中, Sn2+离子发射光谱是峰值位于461 nm宽带谱, 归属于Sn2+离子的3P1→1S0能级跃迁, SZ2P:Mn2+激发光谱由基质吸收带(200–300 nm)和位于352, 373, 419, 431和466 nm的一系列激发峰组成, 分别对应Mn2+离子的6A1(6S)→4E(4D), 6A1(6S)→4T2(4D), 6A1(6S)→[4A1(4G), 4E(4G)], 6A1(6S)→4T2(4G)和6A1(6S)→4T1(4G)能级跃迁, 因此, SZ2P:Sn2+ 的发射光谱与SZ2P:Mn2+的激发光谱有较大范围的重叠. 结果表明Sn2+对Mn2+发光有明显的敏化作用. 基于Dexter电多极相互作用能量传递公式和Reisfeld近似原理分析, 荧光粉SZ2P:Sn2+, Mn2+中Sn2+-Mn2+离子之间的能量传递机理属于电四极-电四极相互作用引起的共振能量传递, 并计算出Sn2+-Mn2+离子之间能量传递临界距离Rc ≈ 1.78 nm. 通过改变Sn2+, Mn2+离子掺杂浓度, 实现了荧光粉发光颜色的调节, 在254 nm短波紫外激发下荧光粉发出较强的蓝白光. 研究结果表明SZ2P:Sn2+, Mn2+荧光粉有望应用于紧凑型节能灯照明领域, 随着半导体紫外芯片技术的发展, 有潜力应用于未来的白光发光二极管照明领域. 相似文献
45.
We explore the possibility of an N-qubit (N>3) Grover
search in cavity QED, based on a fast operation of an N-qubit
controlled phase-flip with atoms in resonance with the cavity mode.
We demonstrate both analytically and numerically that our scheme
can be achieved efficiently to find a marked state with high
fidelity and high success probability. As an example, a ten-qubit
Grover search is simulated specifically under the discussion of
experimental feasibility and challenge. We argue that our scheme is
applicable to the case involving an arbitrary number of qubits. As
cavity decay is involved in our quantum trajectory treatment, we
can analytically understand the implementation of a Grover search
subject to dissipation, which will be very helpful for relevant
experiments. 相似文献
46.
Wan-Li He Meng Li Sheng-Qiang Liu Mei-ju Wei Chang Liu Liao-Liao Li 《Liquid crystals》2018,45(3):370-380
A series of chiral azobenzene compounds with branched terminal were synthesised, and the photosensitive performances were investigated accordingly. It was found that the photochemical properties were mainly affected by the trans–cis configuration of azobenzene and the linked position between the azobenzene and chiral centre. The para-type azobenzenes showed general photochemical decrease in helical twisting power (HTP), but the meta-type ones appeared interestingly showed photochemical increase in HTP. This work provided an effective method for designing molecules to control blue phase (BP) including adjusting colours, inducing BP and extending BP range, which was promising in the applications of optically addressable devices. 相似文献
47.
萘在三氟化硼乙醚溶液中的电化学聚合 总被引:3,自引:0,他引:3
电化学聚合是制备许多电子型导电高分子的有效方法,如合成聚吡咯、聚噻吩、聚呋喃、聚苯等,但对聚萘的报道甚少,并且几乎都采用氯化亚铜的复合催化剂作为电解质。近来我们发现强路易斯酸BF_3的乙醚溶液既是萘的良好溶剂,又是其电化学聚合反应的良好催化剂。将萘溶解于三氯化硼乙醚溶液后,在2V(υs.Ag/AgCl)的外加电压作用下 相似文献
48.
49.
Rashid Mohammed Zi-Feng Zhang Ze Kan Chao Jiang Li-Yan Liu Wan-Li Ma Wei-Wei Song Anatoly Nikolaev Yi-Fan Li 《Molecules (Basel, Switzerland)》2021,26(9)
This paper assesses the occurrence, distribution, source, and toxicity of polycyclic aromatic hydrocarbons (PAHs), and their methylated form (Me-PAHs) in sewage sludge from 10 WWTPs in Northeastern China was noted. The concentrations of ∑PAHs, ∑Me-PAHs ranged from 567 to 5040 and 48.1 to 479dw, which is greater than the safety limit for sludge in agriculture in China. High and low molecular weight 4 and 2-ring PAHs and Me-PAHs in sludge were prevalent. The flux of sludge PAHs and Me-PAHs released from ten WWTPs, in Heilongjiang province, was calculated to be over 100 kg/year. Principal component analysis (PCA), diagnostic ratios and positive matrix factorization (PMF) determined a similar mixed pyrogenic and petrogenic source of sewage sludge. The average values of Benzo[a]pyrene was below the safe value of 600 dependent on an incremental lifetime cancer risk ILCR of 10−6. Sludge is an important source for the transfer of pollutants into the environment, such as PAHs and Me-PAHs. Consequently, greater consideration should be given to its widespread occurrence. 相似文献
50.
通常认为聚苯乙烯具有立体规整度的构型才能结晶,无规聚苯乙烯一般不能结晶。我们用液氮急冷浓度低于体积收缩浓度的无规聚苯乙烯溶液,再将溶剂在真空中升华,得到的粉末状样品含有六角晶系的多晶及单晶。这一发现对研究高分子聚集态结构有重要意义。 相似文献