无需Wondows活动窗口进行音量控制

引言 我工作时喜欢有点背景音乐，会打开Windows Media Player，按下PLAY键来播放音乐。但有电话打进来时，我希望能不用鼠标在桌面上到处找Media Player图标来调低音量或按暂停键。另外，我还有一个朋友抱怨在用PC机玩视频游戏时，游戏会占据整个屏幕，因此调整音量非常麻烦。     

Amplification of Cerenkov Luminescence Using Semiconducting Polymers for Cancer Theranostics

The therapeutic efficacy of photodynamic therapy is limited by the ability of light to penetrate tissues. Due to this limitation, Cerenkov luminescence (CL) from radionuclides has recently been proposed as an alternative light source in a strategy referred to as Cerenkov radiation-induced therapy (CRIT). Semiconducting polymer nanoparticles (SPNs) have ideal optical properties, such as large absorption cross-sections and broad absorbance, which can be utilized to harness the relatively weak CL produced by radionuclides. SPNs can be doped with photosensitizers and have ≈100% energy transfer efficiency by multiple energy transfer mechanisms. Herein, an optimized photosensitizer-doped SPN is investigated as a nanosystem to harness and amplify CL for cancer theranostics. It is found that semiconducting polymers significantly amplify CL energy transfer efficiency. Bimodal positron emission tomography (PET) and optical imaging studies show high tumor uptake and retention of the optimized SPNs when administered intravenously or intratumorally. Lastly, it is found that photosensitizer-doped SPNs have excellent potential as a cancer theranostics nanosystem in an in vivo tumor therapy study. This study shows that SPNs are ideally suited to harness and amplify CL for cancer theranostics, which may provide a significant advancement for CRIT that are unabated by tissue penetration limits.     

The Effect of Nanotube Content and Orientation on the Mechanical Properties of Polymer–Nanotube Composite Fibers: Separating Intrinsic Reinforcement from Orientational Effects

We have measured the mechanical properties of coagulation‐spun polymer–nanotube composite fibers. Both the fiber modulus, Y, and strength, σ_B, scale linearly with volume fraction, V_f, up to V_f ～10%, after which these properties remain constant. We measured dY/dV_f = 254 GPa and dσ_B/dV_f = 2.8 GPa in the linear region. By drawing fibers with V_f < 10% to a draw ratio of ～60%, we can increase these values to dY/dV_f = 600 GPa and dσ_B/dV_f = 7 GPa. Raman measurements show the Herman's orientation parameter, S, to increase with drawing, indicating that significant nanotube alignment occurs. Raman spectroscopy also shows that the nanotube effective modulus, Y_Eff, also increases with drawing. We have calculated an empirical relationship between the nanotube orientation efficiency factor, η_o, and S. This allows us to fit the data for Y_Eff versus η_o, showing that the fiber modulus scales linearly with η_o, as predicted theoretically by Krenchel. From the fit, we estimate the nanotube modulus to be; Y_NT = 480 GPa. Finally, we show that the fiber strength also scales linearly with η_o, giving an effective interfacial stress transfer of τ = 40 MPa and a nanotube critical length of l_c=1250 nm. This work demonstrates the validity of the Cox‐Krenchel rule of mixtures and shows that continuum theory still applies at the near‐molecular level.     

Evaluation of Quantum Efficiency,Crosstalk, and Surface Recombination in HgCdTe Photon-Trapping Structures

The quantum efficiency (QE) in HgCdTe photovoltaic pixel arrays employing a photon-trapping (PT) structure realized with a periodic array of pillars intended to provide broadband operation was investigated. It was found that the QE depends heavily on the passivation of the pillar surface. This is due to the presence of large fixed positive charge on the surface of pillars passivated with anodic oxide. A three-dimensional numerical simulation model was used to study the effect of the surface charge density and surface recombination velocity on the exterior of the pillars. Then, the QE of this structure was evaluated subject to different surface conditions. It was found that alone the surface charge density or surface recombination is detrimental to the QE but that the QE is recovered when both phenomena are present. Subsequently, the crosstalk was analyzed and the superior performance of the PT structure was demonstrated by evaluating the modulation transfer function.     

Optical parametric oscillators

Recent developments in β-barium borate (BBO), lithium triborate (LBO), and potassium titanyl phosphate (KTP) optical parametric oscillators are reviewed. It is noted that, with suitable nonlinear optical crystals and pump sources, virtually any wavelength ranging from the UV to the mid IR can now be reached with optical parametric oscillators. The technology is better developed at the present time for the near-UV to 4.5 μm range, however, largely due to the availability of large, high-quality BBO, LBO, MgO:LiNbO₃, and KTP crystals. For the 1-10 μm range, AgGaS₂ and AgGaSe ₂ show great promise     

A Distribution Management System for Relational Databases in Cloud Environments

For a transaction processing system to operate effectively and efficiently in cloud environments, it is important to distribute huge amount of data while guaranteeing the ACID (atomic, consistent, isolated, and durable) properties. Moreover, database partition and migration tools can help transplanting conventional relational database systems to the cloud environment rather than rebuilding a new system. This paper proposes a database distribution management (DBDM) system, which partitions or replicates the data according to the transaction behaviors of the application system. The principle strategy of DBDM is to keep together the data used in a single transaction, and thus, avoiding massive transmission of records in join operations. The proposed system has been implemented successfully. The preliminary experiments show that the DBDM performs the database partition and migration effectively. Also, the DBDM system is modularly designed to adapt to different database management system (DBMS) or different partition algorithms.     

Gas Diffusion,Energy Transport,and Thermal Accommodation in Single‐Walled Carbon Nanotube Aerogels

The thermal conductivity of gas‐permeated single‐walled carbon nanotube (SWCNT) aerogel (8 kg m^?3 density, 0.0061 volume fraction) is measured experimentally and modeled using mesoscale and atomistic simulations. Despite the high thermal conductivity of isolated SWCNTs, the thermal conductivity of the evacuated aerogel is 0.025 ± 0.010 W m^?1 K^?1 at a temperature of 300 K. This very low value is a result of the high porosity and the low interface thermal conductance at the tube–tube junctions (estimated as 12 pW K^?1). Thermal conductivity measurements and analysis of the gas‐permeated aerogel (H₂, He, Ne, N₂, and Ar) show that gas molecules transport energy over length scales hundreds of times larger than the diameters of the pores in the aerogel. It is hypothesized that inefficient energy exchange between gas molecules and SWCNTs gives the permeating molecules a memory of their prior collisions. Low gas‐SWCNT accommodation coefficients predicted by molecular dynamics simulations support this hypothesis. Amplified energy transport length scales resulting from low gas accommodation are a general feature of CNT‐based nanoporous materials.     

用无线传感器组成无线传感器网络

物联网的愿景之一是能够测量以前从未测量过的变量。无论应用是监视基础设施老化(例如桥梁、隧道或电力传输线的老化),还是实时提供停车及交通信息,都需要无线传感器网络(WSN)提供与有线网络类似的性能,而且适合实际部署。传感器网络要能够扩展至包含大量无线节点,而且在很多情况下,需要跨越很长的距离。     

开放源代码与开放性标准之辨

长期以来，技术供应商在使用“开放”一词的同时，也在滥用它。因此，现在轮到技术用户大量使用开放一词，也就不足为奇了。如今，“开放”一词已经和软件源代码、工业标准、开发商社团和各种许可模型等四个完全不同的技术术语联系在一起。而这四个技术术语经常被人们以含糊的方式混为一谈。软件源代码、工业标准、开发商社团和许可模型都在发挥着各自的作用。但重要的是应该了解到，其中每一种技术指的是什么、不是什么。在这四种技术中，开放性标准最为关键，因为你今天做出的选择不应该妨碍你明天做出另外一种选择。这就是开放性标准的全…     

Thermal modelling of Ohmic heating microreactors

This paper describes the static and transient thermal modelling of an Ohmic heating microreactor for biological sample processing for the purpose of genetic analysis. Precise thermal management can be used for the effective preparation of analyte DNA molecules prior to detection. Due to the small dimensions of the microreactor, the direct measurement and monitoring of the temperature distribution presents a challenge. To overcome this, thermal modelling has been used to accurately predict the thermal behaviour of the microreactor and sample component. It is further possible to calculate the required input power levels and provide design criteria to optimise the design of the microreactor.