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1.
《中国化学快报》2020,31(12):3027-3040
The tumor microenvironment (TME) significantly influences cancer evolution and therapeutic efficacy. Targeting biofunctional molecules to the TME has long been appreciated as a means of raising local drug concentrations and reducing systemic toxicities. The booming nanotechnology field has realized the importance of cathepsin B to derive a variety of intelligent enzyme-responsive nanosized drug delivery systems (nanoDDS) to improve treatment responses and clinical outcomes. In this tutorial review, after introducing the molecular structure and physiological/pathological functions of cathepsin B, the outstanding achievements of cathepsin B-responsive nanoplatforms in the precise diagnosis, targeted therapy, and synergistic theranostics of malignant tumors are systematically described. Finally, the challenges of enzyme-substrate incompatibility, low diagnostic sensitivity, mass production and biocompatibility of multifunctional nanoDDS are considered in order to successfully promote them to clinical applications  相似文献   
2.
In this paper, we propose a novel methodology for automatically finding new chaotic attractors through a computational intelligence technique known as multi-gene genetic programming (MGGP). We apply this technique to the case of the Lorenz attractor and evolve several new chaotic attractors based on the basic Lorenz template. The MGGP algorithm automatically finds new nonlinear expressions for the different state variables starting from the original Lorenz system. The Lyapunov exponents of each of the attractors are calculated numerically based on the time series of the state variables using time delay embedding techniques. The MGGP algorithm tries to search the functional space of the attractors by aiming to maximise the largest Lyapunov exponent (LLE) of the evolved attractors. To demonstrate the potential of the proposed methodology, we report over one hundred new chaotic attractor structures along with their parameters, which are evolved from just the Lorenz system alone.  相似文献   
3.
Structural and optical properties of 1 at % Al-doped Zn1−xMgxO (x=0–8%) powders prepared by sol–gel method were systematically investigated by means of X-ray diffraction, scanning electron microscopy, ultraviolet–visible absorbance measurement, photoluminescence and Raman scattering spectra. All the powders retained the hexagonal wurtzite structure of ZnO. The band gap and near band emission energies determined from absorbance and photoluminescence spectra increased linearly with increasing Mg content, respectively, which implied that the Mg worked effectively on ZnO band gap engineering, irrespective of Al codoping. However, according to the PL and Raman scattering studies, for the sample of x=8%, the Al doping efficiency was decreased by higher Mg codoping. On the other hand, the effect of Mg codoping on photocatalytic degradation of methylene orange was explored experimentally. The substitution of Mg ions at Zn sites shifted the conduction band toward higher energies and then enhanced the photocatalytic activity, while the incorporation of interstitial Mg ions and decreased Al doping efficiency for higher Mg doping sample (x=8%) reduced the photocatalytic activity.  相似文献   
4.
5.
The composition of soluble algal products was visualized by a fingerprint analytical method.  相似文献   
6.
戴鹏  廖同庆 《光谱实验室》2012,29(5):3252-3255
采用不完全相变内耗测量法研究了Cu-13.9Al-4Ni合金在热弹性马氏体相变时其相变内耗峰与外界变量的依赖关系.当测量频率较低时,完全相变法所测量的单一内耗峰被成功分解成双峰,即高温内耗峰和低温内耗峰.低温内耗峰位置对应于相对动力学模量的最小值,高温内耗峰则对应于相对动力学模量的拐点位置,且呈现出明显的反常振幅效应.  相似文献   
7.
A sample of Gd2CuO4 (GCO) has been prepared through the solid state reaction technique. Dielectric properties of this material have been measured in detail as functions of temperature (between 285 and 450 K) and frequency (20 Hz-10 MHz). A step-like increase below 330 K and a broad peak around 360 K were observed in the real part of the permittivity (ε′) which were found to be originated from the oxygen vacancy hopping motions that cause a dipolar relaxation, followed by a Maxwell-Wagner relaxation as the hopping carriers are blocked by the interfaces and surfaces of the sample.  相似文献   
8.
In this work, a novel scheme is proposed to realize joint remote preparation regarding a class of four-qubit cluster-like entangled states based on optimal positive operator-valued measurements. To obtain the preparation of desired states, two tripartite non-maximally entangled states are taken as quantum channels, and devoted to building the robust connections amongst the states’ senders and receiver. It turns out that the present scheme enables one to achieve joint remote state preparation with certain success probability (SP) and unit fidelity. Moreover, several nontrivial issues are discussed, including the improvement of SP and the correlation between SP and the employed channels.  相似文献   
9.
A new metal complex[MnL2](NO32·CH3CN(1) was synthesized by reaction of 4’-4-(l,2,4-triazol-l-yl)phenyl -2,2’:6’,2"-terpyridine(L) with manganese nitrate.The structure of the complex was determined by X-ray crystallography.The results of UV-vis studies showed that the complex exhibits colorimetric sensing ability for Fe3+,which can be observed by naked eye.  相似文献   
10.
L. Li  D. X. Ren  X. Q. Wu  Q. Ge  S. Huang  B. L. Yu 《Laser Physics》2012,22(12):1847-1850
A novel configuration of fiber ring laser acoustic sensor, which adopts single-mode fiber as sensing element, is proposed and demonstrated. Linewidth less than 1 kHz is achieved by introducing a segment of erbium-doped fiber in the reflecting arm as saturable absorber. A polarization independent unbalanced Michelson interrogation interferometer and phase generated carrier demodulation technique are adopted to recover signal. Experiments demonstrate that the phase sensitivity is 0.018 rad/nm in good linearity and equivalent minimum detect able length change reaches 19.1 pm.  相似文献   
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