438 resultados para B-2BF


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工业的高速发展使地球上有限的水资源受到日益严重的污染,去除水中的有毒、有害化学物质已成为环保领域的一项重要工作。纳米材料与技术的开发应用为实现高效、低成本的水处理开辟了新的途径。 本课题组开发的纳米-亚纳米功能新材料(生态宝)可用作养殖生态环境改良剂,它对“三氮”、硫化物、CODCr、BOD5、重金属等有害物质具有很好的去除能力。生态宝用于养殖幼参,有显著的促生长、增加成活率的作用。生态宝用于养殖对虾,对虾体内重金属含量有明显降低。 以粉末状P25型纳米TiO2为光催化剂,系统的研究了它对染料AB80的光催化降解。在紫外光照射下,光催化反应75min,染料AB80溶液完全脱色,光催化反应135min,染料溶液完全矿化;AB80的光催化脱色反应遵从准一级反应动力学;催化剂的最佳剂量为1.0g/L。AB80在TiO2颗粒表面的吸附符合Langmuir方程式,随着pH值的增加吸附量迅速减少;pH值在反应中起着重要的作用,碱性溶液中的反应速度比酸性溶液的大,pH=10.0初始反应速度最大;电子捕获剂(H2O2)的加入能够显著的提高反应速率,H2O2浓度为5mmol/L时,反应速度变为原来的2.78倍。 以硅藻土为载体,采用溶胶-凝胶法制备了负载型的纳米TiO2,SEM分析结果表明,TiO2的包覆量对负载光催化剂的形貌有很大影响,TiO2包覆量较低(14.5%)的复合物无团聚现象发生。XRD分析结果表明,所制备的TiO2为锐钛矿和金红石混晶型,平均粒径11nm。FT-IR分析结果表明,TiO2和硅藻土之间没有生成化学键。以染料AB80和B-2BF为模型污染物,利用制备的光催化剂复合物进行了吸附-光催化试验,结果表明,TiO2包覆量为14.5%的复合物具有较高的吸附-光催化活性,对模型污染物的降解效果好于德国Degussa公司的商品纳米P25-TiO2。溶液pH对TiO2/硅藻土复合物光催化活性影响很大,弱酸性条件有利于反应的进行。TiO2/硅藻土对实际印染废水有较好的降解效果,试验条件下,废水光催化反应3.5h,色度去除率为100%。研究了液固多相光催化反应的催化剂失活原因及再生手段,提出TiO2/硅藻土复合物再生的方法为酸洗和高温烧结。对于模拟印染废水来说,光催化剂重复使用对光催化活性几乎没有影响,重复使用15次后,催化活性仅降低了12%。而对实际印染废水来说,重复使用对光催化活性有影响,光催化剂复合物重复使用7次后,催化活性降低了41%。TiO2/硅藻土复合光催化剂成本低,简便易行,光催化效果好,有望在环境污染物治理中得到广泛的应用。 采用CuCl水解法制得了硅藻土负载的纳米Cu2O,并利用XRD、SEM等手段对其进行表征。研究了负载的纳米Cu2O对B-2BF和AB80染料废水的光催化降解,发现纳米Cu2O经过负载后,团聚减少,分散性好,对染料废水的光催化降解效率成倍增长。纳米Cu2O包覆量为31.3%的光催化剂复合物光催化活性最好,其光催化效率是纯的Cu2O的6倍。负载的纳米Cu2O可以有效的利用太阳光进行光催化反应,而且太阳光下纳米Cu2O的光催化活性比纳米TiO2的强。太阳能是取之不尽、用之不竭的清洁能源,利用太阳能来处理染料废水成本低、无污染,是一种非常有发展前景的环境治理新技术。pH 5-pH 7是负载纳米Cu2O光催化降解B-2BF的最佳反应范围。负载的纳米Cu2O光催化剂有较好的稳定性,重复使用8次以后,其脱色率仍能达到75%以上。

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A Ni-B coating was prepared with EN using potassium borohydride reducing agent. The as-plated micro-structure of the coating was confirmed from XRD to be a mixture of amorphous and supersaturated solid solution. Three kinds of phase transformation were observed from the DSC curve. Different from the previous works, the formation of Ni4B3 and Ni2B was found during some transformation processes. The key factors which influence the variation of micro-hardness and micro-structure in deposits are the formation, the size and amount of Ni3B, Ni4B3 and Ni2B. Aging of the deposits treated under some heat treatment conditions occurred at room temperature. Changes of the micro-hardness indicated aging phenomena evidently. the natural aging phenomena are concerned with various kinds of decomposition of borides, especially with Ni4B3 phase. The extent of natural aging depends on the formation and the quantity of Ni(4)B3 and Ni2B.

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In the present paper the rarefied gas how caused by the sudden change of the wall temperature and the Rayleigh problem are simulated by the DSMC method which has been validated by experiments both in global flour field and velocity distribution function level. The comparison of the simulated results with the accurate numerical solutions of the B-G-K model equation shows that near equilibrium the BG-K equation with corrected collision frequency can give accurate result but as farther away from equilibrium the B-G-K equation is not accurate. This is for the first time that the error caused by the B-G-K model equation has been revealed.

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We present in this paper the application of B-P constitutive equations in finite element analysis of high velocity impact. The impact process carries out in so quick time that the heat-conducting can be neglected and meanwhile, the functions of temperature in equations need to be replaced by functions of plastic work. The material constants in the revised equations can be determined by comparison of the one-dimensional calculations with the experiments of Hopkinson bar. It can be seen from the comparison of the calculation with the experiment of a tungsten alloy projectile impacting a three-layer plate that the B-P constitutive equations in that the functions of temperature were replaced by the functions of plastic work can be used to analysis of high velocity impact.

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Cell adhesion is crucial to many biological processes, such as inflammatory responses, tumor metastasis and thrombosis formation. Recently a commercial surface plasmon resonance (SPR)-based BIAcore biosensor has been extended to determine cell binding mediated by surface-bound biomolecular interactions. How such cell binding is quantitatively governed by kinetic rates and regulating factors, however, has been poorly understood. Here we developed a novel assay to determine the binding kinetics of surface-bound biomolecular interactions using a commercial BIAcore 3000 biosensor. Human red blood cells (RBCs) presenting blood group B antigen and CM5 chip bearing immobilized anti-B monoclonal antibody (mAb) were used to obtain the time courses of response unit, or sensorgrams, when flowing RBCs over the chip surface. A cellular kinetic model was proposed to correlate the sensorgrams with kinetic rates. Impacts of regulating factors, such as cell concentration, flow duration and rate, antibody-presenting level, as well as pH value and osmotic pressure of suspending medium were tested systematically, which imparted the confidence that the approach can be applied to kinetic measurements of cell adhesion mediated by surface-bound biomolecular interactions. These results provided a new insight into quantifying cell binding using a commercial SPR-based BIAcore biosensor.

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本文提出基于浏览器/服务器(Browser/Server简写为B/S)海洋平台结构的远程监测控制系统,实现在客户端不间断对平台进行实时监视,获得现场采集数据,并以图形方式进行实时显示,从而为平台的安全运行和结构设计提供科学依据。

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本文对点火与增长化学反应速率模型进行了改进,采用DYNA2D程序对铸装B炸药的隔板实验过程以及热点的作用进行了二维数值模拟,并和实验结果进行了对照。

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A biosensor based on imaging ellipsometry (BIE) has been developed and validated in 169 patients for detecting five markers of hepatitis B virus (HBV) infection. The methodology has been established to pave the way for clinical diagnosis, including ligand screening, determination of the sensitivity, set-up of cut-off values (CoVs) and comparison with other clinical methods. A matrix assay method was established for ligand screening. The CoVs of HBV markers were derived with the help of receiver operating characteristic curves. Enzyme-linked immunosorbent assay (ELISA) was the reference method. Ligands with high bioactivity were selected and sensitivities of 1 ng/mL and 1 IU/mL for hepatitis B surface antigen (HBsAg) and surface antibody (anti-HBs) were obtained respectively. The CoVs of HBsAg, anti-HBs, hepatitis B e antigen, hepatitis B e antibody and core antibody were as follows: 15%, 18%, 15%, 20% and 15%, respectively, which were the percentages over the values of corresponding ligand controls. BIE can simultaneously detect up to five markers within 1 h with results in acceptable agreement with ELISA, and thus shows a potential for diagnosing hepatitis B with high throughput.

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An analytical fluid model for JxB heating during the normal incidence by a short ultraintense linearly polarized laser on a solid-density plasma is proposed. The steepening of an originally smooth electron density profile as the electrons are pushed inward by the laser is included self-consistently. It is shown that the JxB heating includes two distinct coupling processes depending on the initial laser and plasma conditions: for a moderate intensity (a <= 1), the ponderomotive force of the laser light can drive a large plasma wave at the point n(e)=4 gamma(0)n(c) resonantly. When this plasma wave is damped, the energy is transferred to the plasma. At higher intensity, the electron density is steepened to a high level by the time-independent ponderomotive force, n(e)> 4 gamma(0)n(c), so that no 2 omega resonance will occur, but the longitudinal component of the oscillating ponderomotive field can lead to an absorption mechanism similar to "vacuum heating." (c) 2006 American Institute of Physics.

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通过对非线性薛定谔方程的求解,数值模拟了高功率激光系统中钕玻璃的B积分传输规律,并理论分析了B积分对光脉冲的波形和频谱的影响,详细介绍了几种消除B积分影响的方法。这对高功率激光系统中光放大有一定指导意义。

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Photoluminescence of undoped and B-doped ZnO in silicate glasses was investigated by varying the concentration of ZnO (3550 mol%) and B dopant (0-10 mol%) in the glass matrices. The broad and intense near band edge emissions were observed while the visible light emission was very weak. UV luminescence in all samples was red-shifted relative to the exciton transition in bulk ZnO and enhanced by decreased ZnO concentration due to higher degree of structural integrity and the lower aggregation degree of ZnO. Donor B dopant played the double roles of filling conduction bands to broaden band gap when its concentration was lower than 5 mol%, and emerging with conduction bands to narrow the gap when B dopant exceeded this value. (c) 2007 Elsevier B.V. All rights reserved.

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目的:用新研制的光纤生物传感器FOB-3检测多种病原微生物及细菌毒素.方法:利用双抗体夹心法,优化免疫反应的时间和浓度后,用FOB-3分别检测炭疽芽孢及繁殖体、鼠疫F1抗原和葡萄球菌肠毒素B.为便于结果判定,确定截断(cutoff)值,并以Ssignal与NNnoise差值的形式消除荧光信号中的噪声.结果:使用光纤生物传感器FOB-3,在20 min内可分别检测到50~1000 ng/mL的鼠疫F1抗原、0.1~100μg/mL的葡萄球菌肠毒素B、3×10^1~3×10^6 CFU/mL的炭疽杆菌繁殖体和

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Broadband infrared luminescence covering the optical telecommunication wavelength region of 0, E and S bands was observed in GeO2: Bi, M (M = Ga, B) glasses prepared by conventional melting-quenching technique. The luminescence with a maximum at around 1320 nm possesses a full width at half maximum larger than 300 nm and mean fluorescent lifetime longer than 500 mus when excited by an 808 nm-laser. These glasses may have potential applications in widely tunable laser and super-broadband optical amplifier for the optical communications. (C) 2005 Elsevier B.V. All rights reserved.