Low complexity quantum private queries protocol

Private information retrieval(PIR) is an important privacy protection issue of secure multi-party computation, but the PIR protocols based on classical cryptography are vulnerable because of new technologies,such as quantum computing and cloud computing. The quantum private queries(QPQ) protocols available, however, has a high complexity and is inefficient in the face of large database. This paper, based on the QKD technology which is mature now, proposes a novel QPQ protocol utilizing the key dilution and auxiliary parameter. Only N quits are required to be sent in the quantum channel to generate the raw key, then the straight k bits in the raw key are added bitwise to dilute the raw key, and a final key is consequently obtained to encrypt the database. By flexible adjusting of auxiliary parameters θ and k, privacy is secured and the query success ratio is improved. Feasibility and performance analyses indicate that the protocol has a high success ratio in first-trial query and is easy to implement, and that the communication complexity of O(N) is achieved.     

Insights into low-carbon hydrogen production methods: Green,blue and aqua hydrogen

The primary aim of this study is to provide insights into different low-carbon hydrogen production methods. Low-carbon hydrogen includes green hydrogen (hydrogen from renewable electricity), blue hydrogen (hydrogen from fossil fuels with CO₂ emissions reduced by the use of Carbon Capture Use and Storage) and aqua hydrogen (hydrogen from fossil fuels via the new technology). Green hydrogen is an expensive strategy compared to fossil-based hydrogen. Blue hydrogen has some attractive features, but the CCUS technology is high cost and blue hydrogen is not inherently carbon free. Therefore, engineering scientists have been focusing on developing other low-cost and low-carbon hydrogen technology. A new economical technology to extract hydrogen from oil sands (natural bitumen) and oil fields with very low cost and without carbon emissions has been developed and commercialized in Western Canada. Aqua hydrogen is a term we have coined for production of hydrogen from this new hydrogen production technology. Aqua is a color halfway between green and blue and thus represents a form of hydrogen production that does not emit CO₂, like green hydrogen, yet is produced from fossil fuel energy, like blue hydrogen. Unlike CCUS, blue hydrogen, which is clearly compensatory with respect to carbon emissions as it captures, uses and stores produced CO₂, the new production method is transformative in that it does not emit CO₂ in the first place. In order to promote the development of the low-carbon hydrogen economy, the current challenges, future directions and policy recommendations of low-carbon hydrogen production methods including green hydrogen, blue hydrogen, and aqua hydrogen are investigated in the paper.     

渣油催化临氢热转化钼铁双金属催化剂的研究

Replacement of precious single metal catalysts with cost-effective, highly-dispersed composite catalysts for catalytic hydrothermal conversion of residue holds tremendous promise for the residue upgrading technologies. Organic metals were added to the feed as the oil-soluble precursors, and transformed into the catalytic active phases in this work. Physical properties and structures of the composite catalysts had been investigated by X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope and transmission electron microscopy. The composite catalysts were found to be highly efficient in the catalytic hydrothermal conversion of both model compound and residue. Increased metal dispersion and synergistic effects of two metals played indispensable roles in such catalytic system. Results showed that under the test conditions in the article, the catalyst had the best catalytic performance when the mass ratio of molybdenum to iron was 1.5.     

无黏结预应力框架结构的拆改加固设计

连续多跨的二层无粘结预应力混凝土框架结构按照改造需要拆成单跨框架结构,且增加一层。某一方向的预应力钢筋将全部切断。通过对多种改造加固方案的比选,最终确定了无粘结预应力钢绞线应力释放和重张拉法。通过与专业施工单位的共同配合,顺利完成了该工程预应力拆除改造关键技术,施工监测表明,通过施工监测表明整个拆改过程变形合理可控。本项目取得了较好的经济效应,且是改造项目中的绿色工程。     

Controlled Secure Direct Communication Protocol via the Three-Qubit Partially Entangled Set of States

In this paper, we first re-examine the previous protocol of controlled quantum secure direct communication of Zhang et al.’s scheme, which was found insecure under two kinds of attacks, fake entangled particles attack and disentanglement attack. Then, by changing the party of the preparation of cluster states and using unitary operations, we present an improved protocol which can avoid these two kinds of attacks. Moreover, the protocol is proposed using the three-qubit partially entangled set of states. It is more efficient by only using three particles rather than four or even more to transmit one bit secret information. Given our using state is much easier to prepare for multiqubit states and our protocol needs less measurement resource, it makes this protocol more convenient from an applied point of view.     

High-rate capability of carbon-coated micron-sized hexagonal TT-Nb2O5 composites for lithium-ion battery

With excellent specific capacity, superior cycle stability, safety and strong practical, Nb₂O₅ has been considered as one of the prospective anode materials for lithium-ion batteries (LIBs). However, current study suggests that Nb₂O₅ electrode materials for LIBs still face the vital issues of low electrical conductivity and poor rate performance. Therefore, carbon-coated TT-Nb₂O₅ materials are designed and synthesized through solid state method in this work, which present high specific capacity (228 mA h g^?1 at 0.2C), satisfactory rate properties (107 mA h g^?1 at 20 C). The outstanding electrochemical property can not only give the credit to the pseudocapacitance effect of TT-Nb₂O₅, but also attribute to introduction of carbon. The homogeneous carbon-coated materials enhance the electrical conductivity, increase the electron transmission speed and alleviate particle crushing. This research not only offers a new method for preparing excellent electrode materials, but also provides a kind of excellent anode material with prospective application for LIBs.     

HMZZX环保型无人值守煤炭联合制样系统研发

根据我国煤炭样品制备技术现状和国内外发展趋势,研究开发了自动化控制无人值守煤炭联合制样系统,并从系统制样程序设计、系统整体结构设计、各单元模块设计、系统性能试验等方面对该系统的主要功能及软硬件结构进行介绍,并从称重单元、输送单元、破碎单元、缩分单元、干燥单元、粉碎单元、样品接收包装单元、除尘清洗单元等重点阐述了各单元模块设计,可实现煤样制备全过程无人化、信息化及样品的安全可追溯,其性能试验符合国标GB 474—2008中的相应要求。     

Research on the identification performance of UHF RFID system considering the correlation of cascaded channel

The identification rate of UHF RFID system was restricted by multipath propagation effects.The system identification performance was studied considering the correlation coefficient between forward and reverse channels.Based on the generalized Rician fading channel model,the analytical expression of identification rate was derived under independent,full correlation and correlation cases.Compared with the existing analysis,the proposed uniform calculation formula of identification rate was for any correlation coefficient and kinds of channel conditions.The numerical computation and Monte-carlo simulations show that the influences of different correlation coefficients,channel conditions,sensitivity and distance on the identification rate.