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101.
熔体塔式造粒法生产尿基复混肥   总被引:2,自引:0,他引:2  
汪家铭 《化肥工业》2007,34(1):32-34,44
化肥企业生产尿基复混肥对于农业科学施肥、提高肥料利用率、避免环境污染及促进企业产品结构调整都具有十分重要的意义。熔体塔式造粒法生产尿基复混肥较之其它方法优越性更为显著,笔者简要介绍该法的生产机理、工艺流程、技术特点、国内现状及产品市场前景等方面的一些情况。  相似文献   
102.
介绍了新桥硫铁矿二步骤回采工艺,并从技术经济角度对该矿所采用的充填料及充填系统进行了探讨。  相似文献   
103.
本文在总结中国实验快堆安装工程施工进度管理工作实践的基础上,对施工进度管理的背景、任务、目标及各个实施环节做了全面的描述和有益的探讨,并提出了一些经过实践检验的改进意见,对类似核工程的施工进度管理具有一定的借鉴意义。  相似文献   
104.
铟(Ⅲ)与钼酸铵和罗丹明B在PVA存在下的酸性水溶液中形成离子缔合物而产生显色反应,该体系的灵敏度高,摩尔吸光系数ε=2.44×105L·mol-1cm-1,离子缔合物稳定性好,至少稳定48h。研究了显色体系的光度特性和30多种共存离子的影响,该法应用于纯锡中痕量铟的测定,结果满意。  相似文献   
105.
The secure operation of autonomous vehicle networks in the presence of adversarial observation is examined, in the context of a canonical double-integrator-network (DIN) model. Specifically, we study the ability of a sentient adversary to estimate the full network’s state, from noisy local measurements of vehicle motions. Algebraic, spectral, and graphical characterizations are provided, which indicate the critical role of the inter-vehicle communication topology and control scheme in achieving security.  相似文献   
106.
Collaboration representation-based classification (CRC) was proposed as an alternative approach to the sparse representation method with similar efficiency. The CRC is essentially a competition scheme for the training samples to compete with each other in representing the test sample, and the training class with the minimum representation residual from the test sample wins the competition in the classification. However, the representation error is usually calculated based on the Euclidean distance between a test sample and the weighted sum of all the same-class samples. This paper exploits alternative methods of calculating the representation error in the CRC methods to reduce the representation residual in a more optimal way, so that the sample classes compete with each other in a closer range to represent the test sample. A large number of face recognition experiments on three face image databases show that the CRC methods with optimized presentation residual achieve better performance than the original CRC, and the maximum improvement in classification accuracy is up to 12 %.  相似文献   
107.
108.
The swollen pore structure of a series of microporous isoporous resins (7.4–140 Å) are investigated with inverse GPC, n-alkylbenzenes and linear polystyrenes being used as probe molecules. The results indicated that, with the lowering of crosslinking degree of isoporous resins, the average pore diameter increased and the pore distribution curve broadened. All pore volume distribution obeyed a log-normal distribution. Based on the linear regression method, the experimental data were fitted to a monotonously declining exponential function and a normal distribution function by a computer, and some important structural parameters such as average pore diameter, pore volume distribution, specific surface area, etc. were obtained. The specific surface area of swollen gels were found much greater than those in the dry state measured by N2 adsorption.  相似文献   
109.
汪庆刚 《佛山陶瓷》2005,15(11):12-13
本文通过模具设计、丝网印刷、淋着色坯浆、抛光等工艺处理,使产品具有较好的立体仿古美学效果。  相似文献   
110.
Bio-cryptography is an emerging security technology which combines cryptography with biometrics. A good bio-cryptosystem is required to protect the privacy of the relevant biometric data as well as achieving high recognition accuracy. Fingerprints have been widely used in bio-cryptosystem design. However, fingerprint uncertainty caused by distortion and rotation during the image capturing process makes it difficult to achieve a high recognition rate in most bio-cryptographic systems. Moreover, most existing bio-cryptosystems rely on the accurate detection of singular points for fingerprint image pre-alignment, which is very hard to achieve, and the image rotation transformation during the alignment process can cause significant singular point deviation and minutiae changes. In this paper, by taking full advantage of local Voronoi neighbor structures (VNSs), e.g. local structural stability and distortion insensitivity, we propose an alignment-free bio-cryptosystem based on fixed-length bit-string representations extracted from modified VNSs, which are rotation- and translation-invariant and distortion robust. The proposed alignment-free bio-cryptosystem is able to provide strong security while achieving good recognition performance. Experimental results in comparison with most existing alignment-free bio-cryptosystems using the publicly-available databases show the validity of the proposed scheme.  相似文献   
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