基于VC++6.0的激光干涉仪PGC实时检测解调算法优化

在激光干涉仪相位载波(PGC)实时检测系统中,保证系统的实时性是一个非常重要的环节。在VC++6.0开发平台下,以C语言作为载体,分析了PGC解调算法的原理,充分利用了VC++多线程技术,将信号采集与处理分开,提高了中央处理器(CPU)的利用率。同时对PGC关键算法尤其是有限冲击响应(FIR)滤波、数值积分以及降采样技术等进行了详细地介绍。经算法优化之后,大大减少了运算数据量,增加了系统的实时性。     

N+P photodetector characterization using the quasi-steady state photoconductance decay method

When a material is irradiated, it becomes more electrically conductive due to the absorption of the electromagnetic radiation. As a result, the number of free electrons and holes changes and raises its electrical conductivity. A simple but interesting phenomenon to characterise a fabricated n⁺p photodetector in order to determine its linearity (photoresponse) and photoconductance was employed. Using the transient decay when the irradiation source is switched off, the minority carrier concentration, effective lifetime and surface recombination velocity present at the surface of the detector were measured.     

智能手机RS-MMC存储卡数据恢复研究

为恢复智能手机存储卡中丢失或损坏的数据,以主流RS-MMC存储卡为例,分析了其物理结构和数据存储原理,针对引起数据损坏的不同原因,提出了对应的数据恢复方法。着重研究了逻辑损坏时的数据恢复流程,详细介绍了利用USBOOT软件进行数据恢复的操作步骤。测试表明该方法数据恢复效果好,可用于个人信息恢复、嫌疑手机取证等场合。     

Local discontinuous Galerkin method for solving an N‐carrier system

In this article, we present local discontinuous Galerkin (LDG) method for solving a model of energy exchanges in an N ‐carrier system with Neumann boundary conditions. This model extends the concept of the well‐known parabolic two‐step model for microheat transfer to the energy exchanges in a generalized N ‐carrier system with heat sources. The energy norm stability and error estimate of the LDG method is proved for solving N ‐carrier system. Some numerical examples are given. The numerical results when compared with the exact solution and other numerical results indicate that the present method is seen to be a very good alternative to some existing techniques for realistic problems. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2011     

Properties of a Graphene Oxide-Balofloxacin Composite and Its Effect on Bacteriostasis

A novel graphene oxide-balofloxacin nanocomposite was synthesized, and the loading and release behavior of fluorescent antibacterial balofloxacin on graphene oxide was investigated. The surface morphologies of the nanocomposite were evaluated using transmission electron microscopy and fluorescence microscopy, and the amount of balofloxacin loaded on graphene oxide reached 160.3 mg/g at the initial balofloxacin concentration of 8.51 µg/ml. The graphene oxide and balofloxacin nanocomposite showed the advantage of a longer release time than many current developed nanoscaled drug carriers, which was probably due to the hydrogen bonding interaction between graphene oxide and balofloxacin. The study of the release liquid of e. coli in vitro bacteriostasis suggests that the graphene oxide-balofloxacin nanocomposite has a superior effect against e. coli.     

天然铁矿石为氧载体的生物质化学链气化制合成气实验研究

在一个小型鼓泡流化床反应器上以Ar气为流化介质,对以天然铁矿石为氧载体的生物质化学链气化制合成气过程进行了研究。考察了反应温度对合成气组分、气体产率、碳转化率以及气化效率的影响,反应时间对合成气组分的影响;探讨了氧载体存在对生物质气化过程的影响。结果表明,天然铁矿石可以作为生物质化学链气化制合成气反应过程的氧载体,代替富氧空气或高温水蒸气作为生物质气化的气化剂;随着温度的升高,产物气体中CO、H₂的浓度逐渐增加,CO₂、CH₄浓度缓慢降低;随着反应时间的延长,合成气中H₂、CO、CH₄的相对浓度缓慢增加,而CO₂相对浓度逐渐降低;氧载体的存在能显著提高气体产率和碳的转化率及气化效率。扫描电镜-能谱(SEM-EDS)分析表明,当超过850 ℃时,铁矿石氧载体颗粒表面烧结现象明显,但反应前后,颗粒表面的成分及含量基本保持不变。     

Solitonic waves in polyene dications and principles of charge carrier localization in π‐conjugated organic materials

The quantum‐chemical investigations by ab initio method (restricted Hartree–Fock/6‐31G**) have been performed for a series of unsubstituted, monosubstituted, and disubstituted neutral polyenes and their double charged cations. The waves of charge alternation (characterized by the difference in the electron densities at the nearest carbon atoms or Δq function) and bond length alternation (characterized by the lengths difference of the nearest carbon–carbon bonds or Δl function) are reported. Comparisons are made with the corresponding monocationic polymethine molecules. We found that ionization by two electrons results in formation of two solitonic waves of charge alternation, rather than superposition of two overlapping solitonic waves into one. These waves behave similar to two independent elastic particles, which do not penetrate into each other despite the special confinement by the length of chromophore π‐system. In monosubstituted polyene dication, Δq and Δl functions contain two waves each; however, only one wave is mobile and sensitive to a change of the chemical nature of the terminal group, whereas the second wave remains practically unchanged. The introduction of one oxymethyl or phenyl terminal groups leads to a relatively small shift of the mobile wave from the center to a direction of the terminal group. The effect of the amino or tropilium terminal groups is much more pronounced and leads to a shift of the mobile wave to the end of the molecule. In disubstituted polyene dication, both solitonic waves become mobile and shift symmetrically to both ends. The general principles of the charge localization described in this study may be used in molecular design and fine‐tuning of the charge transport properties in plastic photovoltaics and other organic semiconducting materials. © 2012 Wiley Periodicals, Inc.     

Simultaneous Spectrophotometric Estimation of Rabeprazole Sodium and Itopride HCl

Abstract

Two simple, rapid, accurate, and economical analytical methods have been developed for the simultaneous estimation of Rabeprazole Sodium and Itopride Hydrochloride in combined capsule dosage form. First method is based on the determination of Q‐value and second method is based on simultaneous equation method. Rabeprazole Sodium has absorbance maxima at 284 nm and Itopride Hydrochloride has absorbance maxima at 258 nm in methanol AR. The absorption ratio (Q‐value) was determined at 266.6 nm (Iso‐bestic point) and 284 nm (λmax of Rabeprazole Sodium). Both the drugs obey Beer's law in the concentration ranges employed for these methods. Both the methods were found to be simple, rapid, accurate, and can be adopted in routine analysis of drugs in formulations. The accuracy and reproducibility of the proposed method was statistically validated by recovery studies     

A scheme for synchronizing clocks connected by a packet communication network

Consider a communication system in which a transmitter equipment sends fixed-size packets of data at a uniform rate to a receiver equipment. Consider also that these equipments are connected by a packet-switched network, which introduces a random delay to each packet. Here we propose an adaptive clock recovery scheme able of synchronizing the frequencies and the phases of these devices, within specified limits of precision. This scheme for achieving frequency and phase synchronization is based on measurements of the packet arrival times at the receiver, which are used to control the dynamics of a digital phase-locked loop. The scheme performance is evaluated via numerical simulations performed by using realistic parameter values.