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91.
Benefitting from the special structure of the leaf cuticle layer, plants have natural hydrophobicity and anti-fouling abilities. Inspired by the leaf surface structure, a biomimetic modification strategy was raised to improve the surface hydrophobicity of polyacrylate coating for controlled release fertilizer. Double-layer (polyacrylate and carnauba wax) coated fertilizer was obtained after biomimetic modification. The quality of controlled release fertilizer modified with the carnauba wax was greatly enhanced, and the coating material was effectively saved. The surface appearance of polyacrylate-coated fertilizer was improved for the surface blemish was repaired by the loaded carnauba wax. The characterizations by Fourier transform infrared spectroscopy indicated that the hydrogen bonds were formed between the water-based polyacrylate membrane and the carnauba wax layers. By optimizing the content of polyacrylate and carnauba wax, the release duration of the fertilizer was effectively prolonged, which was improved from 1 month to more than 2 months after the biomimetic modification. Therefore, biological wax as an environmentally-friendly natural material that has showed a broad potential in the application of coated controlled release fertilizer.  相似文献   
92.
通过我国混凝土空心砌块节能建筑案例分析,提出外保温、内保温、夹芯保温各有优缺点,应因地制宜,依据建筑功能要求采取适合的保温方式,并根据多年的研究和应用实践经验,提出了我国不同气候区域混凝土空心砌块节能建筑的外墙构造设计方案。  相似文献   
93.
浅谈零缺陷与质量成本   总被引:1,自引:0,他引:1  
阐述零缺陷在工作中的行动准则和零缺陷管理所要达到的最终目标,分析了零缺陷在实际生产中对质量成本的影响。  相似文献   
94.
论文根据小型无人直升机的机理建立了数学模型,并在悬停状态下近似线性化,运用Matlab的非线性控制工具箱(NCD)设计了具有很强鲁棒性的控制器,实现了对于小型无人直升机的纵向和横向的解耦控制,仿真结果证明了方法的有效性。  相似文献   
95.
In this paper, we consider the performances in terms of system throughput and response time of various channel-aware scheduling algorithms for both MPEG streams and non-MPEG flows in a high-data-rate (HDR) wireless personal area network (WPAN). The algorithms under investigation are the shortest remaining processing time rule, the exponential rule, the modified largest weighted delay first rule, the maximum rate rule, and the proportionally fair rule. Decodability issues are taken care of by means of the frame-decodability aware technique and the burst transfer eligibility decision mechanism. The impacts of a number of factors including deadline and interference-plus-noise level are also examined. The investigations are carried out through extensive ns-2 simulations. Based on the numerical results, we propose a heuristic scheduling algorithm for MPEG streams that outperforms the above algorithms in terms of system throughput. The findings are useful for system designers.  相似文献   
96.
The objective of this research is to develop a framework named Wise-ShopFloor and the enabling technologies for collaborative manufacturing in a decentralized environment. Particularly, this paper presents our latest development on Web-based and sensor-driven remote machining. Once a product design is given, its process plan and NC codes are generated by using a distributed process planning (DPP) system. The NC codes are then used for remote machining via a standard Web browser and a Java GUI interface running inside the browser. In this paper, the focus is given to the concept, architecture and a prototype implementation of the enabling technology. A case study of a test part machining on a 5-axis milling machine is also completed for testing and validation. It is expected that the developed technology can be applied to design verification via remote machining as well as real part production in a distributed manufacturing environment.  相似文献   
97.
针对红外导引头多元信息探测和实时数据处理要求,设计了基于FPGA和DSP的多通道高速实时数据采集和处理平台;在该平台中,通过FPGA实现了DSP的引导、多通道高速A/D、D/A、大容量存储器(SDRAM和FLASH)和数字I/O等功能模块的无缝链接及逻辑控制;利用时序分配和EDMA(扩展的直接存储器访问)技术以及McBSP(多通道缓冲串口)和HPI(主机口),实现了FPGA和DSP之间实时传输与通信控制;实际应用表明在该平台中A/D与FPGA之间串行传输速率可达20MHz,FPGA与DSP之间串行传输速率可达70MHz,且平台运行稳定、可靠,满足了红外导引头的实时信号处理要求。  相似文献   
98.
丁玉奎  杜志明 《兵工学报》1999,20(4):316-319
建立了对可见光和近红外的瞬态测试记录系统。用实验方法研究了氩气在炸药冲击小励下产生的可见光光强。测得了不同压力下氩气的辐射强度,分析了气体压力对光强的影响。  相似文献   
99.
Plants have evolved a sophisticated defense system that employs various hormone pathways to defend against attacks by insect pests. Cytokinin (CK) plays an important role in plant growth and stress tolerance, but the role of CKs in plant–insect interaction remains largely unclear. Here, we report that CKs act as a positive regulator in rice resistance against brown planthopper (BPH), a devastating insect pest of rice. We found that BPH feeding promotes CK biosynthesis and signaling in rice. Exogenous application of CKs significantly increased the rice resistance to BPH. Increasing endogenous CKs by knocking out cytokinin oxidase/dehydrogenase (OsCKXs) led to enhanced resistance to BPH. Moreover, the levels of the plant hormone jasmonic acid (JA) and the expression of JA-responsive genes were elevated by CK treatment and in OsCKXs knockout plants. Furthermore, JA-deficient mutant og1 was more susceptible to BPH, and CK-induced BPH resistance was suppressed in og1. These results indicate that CK-mediated BPH resistance is JA-dependent. Our findings provide the direct evidence for the novel role of CK in promoting insect resistance, and demonstrate that CK-induced insect resistance is JA-dependent. These results provide important guidance for effective pest management strategies in the future.  相似文献   
100.
As an ATP-dependent DNA helicase, human ChlR1/DDX11 (Chl1 in yeast) can unwind both DNA:RNA and DNA:DNA substrates in vitro. Studies have demonstrated that ChlR1 plays a vital role in preserving genome stability by participating in DNA repair and sister chromatid cohesion, whereas the ways in which the biochemical features of ChlR1 function in DNA metabolism are not well understood. Here, we illustrate that Chl1 localizes to double-strand DNA break (DSB) sites and restrains DNA:RNA hybrid accumulation at these loci. Mutation of Chl1 strongly impairs DSB repair capacity by homologous recombination (HR) and nonhomologous end-joining (NHEJ) pathways, and deleting RNase H further reduces DNA repair efficiency, which indicates that the enzymatic activities of Chl1 are needed in Schizosaccharomyces pombe. In addition, we found that the Rpc37 subunit of RNA polymerase III (RNA Pol III) interacts directly with Chl1 and that deletion of Chl1 has no influence on the localization of Rpc37 at DSB site, implying the role of Rpc37 in the recruitment of Chl1 to this site.  相似文献   
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