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941.
Huiping Hu Jianxiong Hao Yongqiang Cheng Lijun Yin Yanli Ma Zhenwei Yu Lite Li 《International Journal of Food Science & Technology》2012,47(4):689-695
A low‐salt (4% NaCl, w/w) douchi supplemented with different concentration of fermented rice culture (FRC) of 0%, 5%, 10%, 15% and 20% (v/w) was produced, and the effect of FRC on microbiology, biochemistry and sensory quantity was investigated. Results indicated that FRC had a significant effect on low‐salt douchi. Compared with the control (added 0% FRC), in the other treatments, the counts of yeast and lactic acid bacteria increased by about 50%, whereas the moulds decreased by about 30%; the pH reduction was close to 4.7; total acid increased to about 1.300 g per 100 g; reducing sugar maintained a decrease to 21.07 mg per g; amino nitrogen increased to about 0.900 g per 100 g, but not above the control (1.013 g per 100 g). In general terms, total free amino acid contents and three organic acids were higher in low‐salt products than four commercial products. Sensory evaluation of products supplemented with 10% and 15% FRC revealed better overall acceptability compared with other treatments and a commercial product. 相似文献
942.
Xiubin B. Wang Xiaowei Cao Kai Yin Teresa M. Adams 《Networks and Spatial Economics》2017,17(3):713-735
This paper models the relationship between vehicle miles traveled (VMT) on local and collector roads with an objective to predict local road VMT by using collector road VMT. Through a continuous approximation method typically used for vehicle routing, it first analytically reveals this relationship mainly as a function of roadway density ratios between multiple roadway classifications. This structural relationship suggests regression equations using density ratios or logarithmic values of them as the explanatory variables. The use of regression equations enables to account for varying spatial distributions of roadways and demand through parameter calibration. The proposed regression equations are proved good fits through computer simulation using distinct community road network topologies. In addition, practical data from Hennepin County of Minnesota, U.S.A. that encompasses Minneapolis indicates that our developed regression equations can work well. 相似文献
943.
The white-box attack is a new attack context in which it is assumed that cryptographic software is implemented on an un-trusted platform and all the implementation details are controlled by the attackers. So far, almost all white-box solutions have been broken. In this study, we propose a white-box encryption scheme that is not a variant of obfuscating existing ciphers but a completely new solution. The new scheme is based on the unbalanced Feistel network as well as the ASASASA (where “A” means affine, and “S” means substitution) structure. It has an optional input block size and is suitable for saving space compared with other solutions because the space requirement grows slowly (linearly) with the growth of block size. Moreover, our scheme not only has huge white-box diversity and white-box ambiguity but also has a particular construction to bypass public white-box cryptanalysis techniques, including attacks aimed at white-box variants of existing ciphers and attacks specific to the ASASASA structure. More precisely, we present a definition of white-box security with regard to equivalent key, and prove that our scheme satisfies such security requirement. 相似文献
944.
我国房地产业在经济发展中具有重要作用.运用动态因子分析法,侧重从房地产开发和销售的角度对2005-2009年全国31个省市的房地产发展水平进行综合评价,结果表明:从动态的角度来看,全国房地产业发展水平整体呈上升趋势.就横向比较而言,北京房地产开发和销售的综合水平在全国各省区处于领先地位.部分经济发达地区和沿海省区综合排名相对靠前,如天津、广东、福建等.西部地区相对落后,平均综合得分较低,表明房地产业的发展与经济发达程度存在一定的关系.总的来说,全国各地区的房地产业开发和销售的发展状况普遍表现正常,行业发展态势较好. 相似文献
945.
我们在无机化学课程教学中采用了启发式教学模式与思维导图相结合的方法,实现了"以学生为主体,教师为主导"的教学理念。本文通过两个教学案例说明了包含多种教学手段的启发式教学模式及思维导图在教学活动中的运用和教学效果。 相似文献
946.
Guoxin Tan Ying Tan Guoxin Ni Guobo Lan Lei Zhou Peng Yu Jingwen Liao Yu Zhang Zhaoyi Yin Hang Wang Chengyun Ning 《Journal of materials science. Materials in medicine》2014,25(8):1875-1884
To further enhance the biological properties of acid-etched microrough titanium surfaces, titania nanotextured thin films were produced by simple chemical oxidation, without significantly altering the existing topographical and roughness features. The nanotextured layers on titanium surfaces can be controllably varied by tuning the oxidation duration time. The oxidation treatment significantly reduced water contact angles and increased the surface energy compared to the surfaces prior to oxidation. The murine bone marrow stromal cells (BMSCs) were used to evaluate the bioactivity. In comparison, oxidative nanopatterning of microrough titanium surfaces led to improved attachment and proliferation of BMSCs. The rate of osteoblastic differentiation was also represented by the increased levels of alkaline phosphatase activity and mineral deposition. These data indicated that oxidative nanopatterning enhanced the biological properties of the microrough titanium surfaces by modulating their surface chemistry and nanotopography. Based on the proven mechanical interlocking ability of microtopographies, enhancement of multiple osteoblast functions attained by this oxidative nanopatterning is expected to lead to better implant osseointegration in vivo. 相似文献
947.
2010年,山东省防汛形势复杂而严峻,极端天气事件频繁发生,人民群众生命财产安全受到极大威胁,部分地区遭受了较为严重的洪涝灾害,水利工程损坏严重。面对严峻的防汛形势,全省上下在省委、省政府的坚强领导下,扎实准备,主动防御,快速反应,科学防控,全力落实各项措施,确保了全省安全度汛,实现了无一水库垮坝、无一骨干河道决口、无一人因洪死亡的防控目标。 相似文献
948.
Standard is an effective carrier of developing circular economy while standardization is the foundation of scientific management of circular economy and the bridge for scientific research,production and application.Therefore,it is necessary to explore how to give full play to the important roles of standardization in the development of circular economy,how to make use of standardization to accelerate the promotion and application of advanced technology for circular economy and to develop the circular economy with the help of standardization. 相似文献
949.
Yu Zhang Qing-Shui Yin Hua-Fu Zhao Jian Li Yue-Teng Wei Fu-Zhai Cui Hua-Yang Huang 《Frontiers of Materials Science in China》2010,4(4):359-365
The antibacterial and biological properties of silver-loated coralline hydroxyapatite (Ag-CHA) as a new antibacterial implant
material were investigated in this study. Compared to other antibiotic and chemical bactericidal agents, Ag+ does not bring bacterial resistance to drugs and has less toxicity. The porous CHA was formed by hydrothermal exchange, then
Ag+ was loated onto CHA through ion exchange and adsorption. The microstructure and composition of Ag-CHA were characterized
by scanning electron microscopy (SEM), Rutherford backscattering spectrometry (RBS), and energy dispersive spectrometry (EDS).
Antibacterial activity of Ag-CHA on the clinical strains of Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus) was evaluated by the flat plate diffusion method. The antibacterial activity of Ag-CHA was found to be correlated with the
concentration of Ag+ in a dose-dependent manner, which indicated that the optimal antibacterial and biocompatible effects of Ag-CHA could be obtained
with Ag+ concentrations from 5×10−5 to 1×10−4 mol/L. 相似文献
950.