摘要：In the paper, we propose a surface wave suppression method in time-frequency domain based on the wavelet transform, considering the characteristic difference of polarization attributes, amplitude energy and apparent velocity between the effective signals and strong surface waves. First, we use the proposed method to obtain time-frequency spectra of seismic signals by using the wavelet transform and calculate the instantaneous polarizability at each point based on instantaneous polarization analysis. Then, we separate the surface wave area from the signal area based on the surface-wave apparent velocity and the average energy of the signal. Finally, we combine the polarizability, energy, and frequency characteristic to identify and suppress the signal noise. Model and field data are used to test the proposed filtering method.

摘要：人工脉冲神经网络通常由多个异质结构的电路单元构成,其中包括具备积分点火功能来产生脉冲信号的神经元模拟器,以及具备记忆功能的突触器件.在本文中,我们设计了一种能进行“同质集成”的相变存储介质Ge-Ga-Sb(GGS)器件,该器件能够同时实现神经元和突触的模拟.在先前的研究中,GGS材料表现出优秀的数据存储功能,例如它具备较高的工作温度(281℃)、较高的十年数据保存温度(230℃)以及较低的电阻漂移.当对该器件改用短脉冲电学操作时,GGS器件首先会发生几个数量级的电阻突变,然后紧接着发生连续的电阻降低.通过透射电子显微镜发现,电阻突变是因为电极之间产生了结晶的导电通道,而电阻缓变是因为导电通道的变粗以及在通道内产生材料分相所致.这种“突变-缓变”的电阻变化特性既可以用来模拟神经元的积分点火功能,也可以模拟突触权重的变化.基于此器件设计的全相变脉冲神经网络,可以实现高达90%的手写数字识别率.

摘要：Aiming to resolve the technical problems of lower gas concentrations and a reduced effective drainage period caused by gas-drainage borehole fracture development, a flexible gel （FG） gas-drainage borehole sealing material was developed that adapts to borehole deformation. In this study, based on orthogonal tests, the effect of the ratio of material to water, stirring time and stirring speed on the viscosity, filtration property, water retention and pumpability of the FG were studied. The results indicate that the stirring speed, ratio of material to water and stirring time in turn increased the viscosity and the ratio of material to water, stirring time and stirring speed enhanced the filtration property and water retention. The FG pumps smoothly and achieves the optimal state of high water retention, low fluid loss and low viscosity when the ratio of material to water is 1：10, the stirring speed is 800 r/min, and the stirring time is 12 min. The field test results indicate that, after using the FG, the average drainage gas concentration increases by 25.9% and 27.6g and the average negative pressure of extraction increases by 2.7 kPa and 3.5 kPa com- pared with expansive cement and polyurethane, respectively.

摘要：Rapid technological development and population growth are responsible for a series of imminent environmental problems and an ineluctable energy *** application of semiconductor nanomaterials in photocatalysis or photoelectrocatalysis(PEC)for either the degradation of contaminants in the environment or the generation of hydrogen as clean fuel is an effective approach to alleviate these ***,the efficiency of such processes remains suboptimal for real *** construction of a built-in electric field is considered to efficiently enhance carrier separation and reduce carrier recombination to improve catalytic *** the past decade,as a new method to enhance the built-in electric field,the piezoelectric effect from piezoelectric materials has been extensively *** this review,we provide an overview of the properties of piezoelectric materials and the mechanisms of piezoelectricity and ferroelectricity for a built-in electric ***,piezoelectric and ferroelectric polarization regulated built-in electric fields that mediate catalysis are ***,the applications of piezoelectric semiconductor materials are also highlighted,including degradation of pollutants,bacteria disinfection,water splitting for H2 generation,and organic *** conclude by discussing the challenges in the field and the exciting opportunities to further improve piezo-catalytic efficiency.

摘要：Bio-nanochannels in living organisms participate in the physiological activities by selectively transporting ions through cell *** structure and function of biological ion channels inspire the development of artificial ion nanochannels with practical *** bioinspired nanochannels based on polymer materials present good mechanical stability,high-performance ion transport and designability,which have attracted much *** this review,we mainly focus on the fabrication and application of polymer-based biomimetic nanochannels especially in environmentally responsive biosensor and energy *** firstly introduce the basic understanding of nanochannels in ion regulation and osmotic energy ***,we discuss the fabrication methods of polymer-based nanochannels and highlight their advantages compared with other *** practical applications of polymer-based biomimetic nanochannels,especially in energy conversion and environmentally responsive biosensor,are detailedly ***,we summarize the unsolved problems in bioinspired nanochannels and overview the further developing direction in this field.

摘要：Dynamic exploration for oil and gas requires careful monitoring of reservoir contents for safety and efficiency of oil extraction. This paper proposes a multi-source and multi-azimuth walk-around vertical electromagnetic profiling （MM-VEP） technique for surface-to-borehole electromagnetic surveying. Based on the difference in conductivities between reservoirs with different concentrations of oil and water, MM-VEP can be used to monitor reservoirs as they are injected with water. The MM-VEP response in five azimuth planes is modeled with three-dimensional （3D） integral equation calculations. The progress of waterflooding in four stages for enhanced oil recovery is shown to be indicated by field anomalies MM-VEP caused by variations in the reservoir resistivity. Numerical modeling demonstrates that MM-VEP measurements provides enough quantitative information from an underground reservoir to accurately detect oil deposits and monitor the progress of waterflooding.

摘要：目的探讨注射用丹参总酚酸(冻干)(SLI)对人CYP450酶和P-糖蛋白体外抑制作用以及对大鼠CYP1A2和CYP3A体内诱导作用。方法①应用P450-GloTMCYP450检测试剂盒,通过化学发光法测定SLI和经典抑制剂对细胞色素P4501A2(CYP1A2),CYP2D6,CYP3A4,CYP2C19和CYP2C9的IC50值,通过比较SLI和经典抑制剂对相应细胞色素P450亚型的IC50值来判断SLI对人CYP450酶的体外抑制作用。②Wistar大鼠分别iv给予SLI 3,10和30 mg·kg-1和诱导剂苯巴比妥钠20 mg·kg-1,采用探针底物法,通过比较代谢产物的生成速率来评价SLI对大鼠CYP1A2和CYP3A的诱导作用。③应用ATP酶检测试剂盒,通过化学发光法测定ATP酶活性来评价SLI是否为P-gp的底物或抑制剂。结果①CYP1A2,CYP2C9,CYP2C19,CYP2D6和CYP3A4抑制剂的IC50与SLI对其的IC50进行比较(CYP1A2:0.12μmol·L-1vs 840μmol·L-1;CYP2C9:3.362μmol·L-1vs 704μmol·L-1;CYP2C19:3.236μmol·L-1vs 306μmol·L-1;CYP2D6:0.117μmol·L-1vs 2660μmol·L-1;CYP3A4:0.078μmol·L-1vs 1780μmol·L-1)。②与空白对照组(86.4±6.3)nmol·***-1相比,SLI 3,10和30 mg·kg-1组CYP1A2活性分别为83.4±6.6,82.5±4.0和(83.4±6.6)nmol·***-1。与空白对照组(16.1±0.9)nmol·***-1比较,SLI 3,10和30 mg·kg-1组CYP3A活性分别为15.7±0.6,15.9±0.7和(15.9±1.0)nmol·***-1,无显著性差异。③以临床血药浓度为依据设计的一系列浓度的SLI 0.0002,0.0006,0.002,0.006,0.017,0.052,0.156和0.468 g.L-1的ATP酶活性分别与空白对照组进行比较(5.8,5.3,5.8,5.5,5.8,5.2,,5.8,5.3,vs 5.75μmol·***-1),无显著性差异。结论SLI临床给药剂量既不能体外抑制人CYP1A2,CYP2D6,CYP3A4,CYP2C19和CYP2C9酶活性,也不能诱导大鼠CYP1A2和CYP3A,同时也不是P-gp的体外抑制剂或底物。

摘要：设计并制备一种高强度、中等导电性的Cu-1.3Ni-1.2Co-0.7Si-0.3Cr-0.1 Mg合金。研究多级形变热处理对合金组织和性能的影响及其强化机制。结果表明,在时效过程中,高密度位错区和亚晶界处析出大量纳米级的β-Ni_(3)Si、δ-(Ni,Co)_(2)Si和Cr相颗粒,凝固过程中形成亚微米级Cr_(3)Si相。该合金的抗拉强度、屈服强度和电导率分别为882 MPa、857 MPa和46.7%(IACS)。通过强化模型的计算和强度测试,该合金的主要强化机制为析出强化、应变强化和亚结构强化。

摘要：含有锍离子的葡萄糖苷酶抑制剂如kotalanol(SK)和它除去磺酸基团后的衍生物(DSK),是潜在的毒副作用较小的治疗Ⅱ型糖尿病的候选药物.α-葡萄糖苷酶抑制活性实验显示,DSK活性比SK略高,而将二者环上的S原子替换成NH后(分别称为DSN和SN),DSN的活性要比SN高1500倍左右.本文用分子动力学模拟,结合自由能计算和自由能分解的方法对上述四个抑制剂的作用机理进行了研究.研究结果表明活性的巨大差异是由NH基团取代效应和磺酸基团立体效应共同作用的结果,由于N―C键长比S―C键长短,NH基团取代导致烷基链的翻转,同时,磺酸基团限制了链的翻转,因此改变了抑制剂的结合模式.计算结果与实验基本一致.本文的研究结果有助于进一步理解含锍离子的葡萄糖苷酶抑制剂的结合机理,并为设计更有潜力的葡萄糖苷酶抑制剂提供了有价值的信息.

摘要：Currently,most rock physics models,used for evaluating the elastic properties of cracked or fractured media,take into account the crack properties,but not the background *** creats the errors of in the anisotropy estimates by using fi eld logging *** this work,based on the scattered wavefi eld theory,a sphere-equivalency method of elastic wave scattering was developed to accurately calculate the elastic properties of a vertical transversely isotropic solid containing aligned *** setting the scattered wavefi eld due to a crack equal to that due to an equivalent sphere,an eff ective elastic stiff ness tensor was derived for the cracked *** stability and accuracy of the approach were determined for varying background anisotropy *** results show that the anisotropy of the eff ective media is aff ected by cracks and background anisotropy for transversely isotropic background permeated by horizontally aligned cracks,especially for the elastic wave propagating along the horizontal ***,the crack orientation has a signifi cant infl uence on the elastic wave velocity *** theory was subsequently applied to model laboratory ultrasonic experimental data for artifi cially cracked samples and to model borehole acoustic anisotropy *** considering the background anisotropy,the model shows an improvement in the agreement between theoretical predictions and measurement data,demonstrating that the present theory can adequately explain the anisotropic characteristics of cracked media.