中材罗定4 500 t/d熟料线的高效建设和生产管理经验之探讨

中材罗定水泥有限公司一期4 500 t∕d熟料生产线项目,无论从建设工期、项目质量、项目总投资还是投产后的各项经济技术指标,均全面达到了优良的水平。这基于项目设计时,按照先进、节能、节省投资的原则进行工程方案的确定;建设期间,有效控制住了建设进度、工程质量和安全保障;生产期间,又通过强化和细化生产系统的管理,从而确保了全线的高效益生产运行。     

Pressure Drop Models for Gas/Non‐Newtonian Power‐Law Fluids Flow in Horizontal Pipes

Models commonly used in literature are evaluated versus 696 data points to predict the pressure drop of gas/non‐Newtonian power‐law fluids flow in horizontal pipes. Suitable models are recommended. A new correlation is developed by ignoring the pressure drop across the gas slug and adopting the liquid slug holdup of gas/non‐Newtonian fluid flow into the homogeneous model. The theoretical curves can capture the test data trends and the overall agreement of predicted values with experimental data is sufficient to be practically applied in industry.     

Influence of nano‐CeO2 as Co‐stabilizer on the thermal stabilization efficiency of novel calcium/Zinc soap stabilizers for poly(vinyl chloride)

The novel organic calcium (Ca)/zinc (Zn) stabilizer of poly(vinyl chloride) (PVC) was synthesized from poly (zinc methylacrylate) and Ca adipate. The influences of Zn/Ca soap weight ratios and nano‐CeO₂ as co‐stabilizer on the thermal stability of PVC were investigated. Congo red testing, thermogravimetric analysis, dynamic rheology, and dynamic mechanical analysis of the mixtures were performed. The results show that the novel stabilizer has good stabilization efficiency on PVC. When 5 phr (parts by weight per hundred parts of resin) of novel stabilizer (weight ratio of Zn/Ca soap is 6/4) in 100 phr of PVC is used as stabilizer, the Congo red time can reach 192 min, which is 131 min longer than 5 phr of the mixture of 3 phr of Zn stearate and 2 phr of Ca stearate as stabilizer. If 3 phr of mixture of Zn methylacrylate with Ca adipate (weight ratio of Zn/Ca soap is 4/6) and 2 phr of nano‐CeO₂ are used as co‐stabilizers, the Congo red time is 205 min. The combination of nano‐CeO₂ with Ca/Zn soap stabilizer shows an obvious improvement for the thermal stability of the PVC. J. VINYL ADDIT. TECHNOL., 20:243–249, 2014. © 2014 Society of Plastics Engineers     

Structure Evolution and Electrical Properties of Y3+‐Doped Ba1−xCaxZr0.07Ti0.93O3 Ceramics

Lead free piezoelectric ceramics of Y³⁺‐doped Ba_1?xCa_xZr_0.07Ti_0.93O₃ with x = 0.05, 0.10, and 0.15 were prepared. Composition and temperature‐dependent structural phase evolution and electrical properties of as‐prepared ceramics were studied systematically by X‐ray diffraction, Raman spectroscopy, impedance analyzer, ferroelectric test system, and unipolar strain measurement. Composition with x = 0.10 performs a good piezoelectric constant d₃₃ of 363 pC/N, coercive field E_c of 257 V/mm, remanent polarization P_r of 14.5 μC/cm², and a Curie temperature T_m of 109°C. High‐resolution X‐ray diffraction was introduced to indicate presence of orthorhombic phase. Converse piezoelectric constant d₃₃* of x = 0.10 composition performed better temperature stability in the range from 50°C to 110°C. That means decreasing orthorhombic–tetragonal phase transition temperature could be an effective way to enlarge its operating temperature range.     

Nanocrystalline Barium Strontium Titanate Ceramics Synthesized via the “Organosol” Route and Spark Plasma Sintering

Dense nanocrystalline barium strontium titanate Ba_0.6Sr_0.4TiO₃ (BST) ceramics with an average grain size around 40 nm and very small dispersion were obtained by spark plasma sintering at 950°C and 1050°C starting from nonagglomerated nanopowders (~20 nm). The powders were synthesized by a modified “Organosol” process. X‐ray diffraction (XRD) and dielectric measurements in the temperature range 173–313 K were used to investigate the evolution of crystal structure and the ferroelectric to paraelectric phase transformation behavior for the sintered BST ceramics with different grain sizes. The Curie temperature T_C decreases, whereas the phase transition becomes diffuse for the particle size decreasing from about 190 to 40 nm with matching XRD and permittivity data. Even the ceramics with an average grain size as small as 40 nm show the transition into the ferroelectric state. The dielectric permittivity ε shows relatively good thermal stability over a wide temperature range. The dielectric losses are smaller than 2%–4% in the frequency range of 100 Hz–1 MHz and temperature interval 160–320 K. A decrease in the dielectric permittivity in nanocrystalline ceramics was observed compared to submicrometer‐sized ceramics.     

Transplanted Neural Stem Cells Modulate Regulatory T, γδ T Cells and Corresponding Cytokines after Intracerebral Hemorrhage in Rats

The immune system, particularly T lymphocytes and cytokines, has been implicated in the progression of brain injury after intracerebral hemorrhage (ICH). Although studies have shown that transplanted neural stem cells (NSCs) protect the central nervous system (CNS) from inflammatory damage, their effects on subpopulations of T lymphocytes and their corresponding cytokines are largely unexplored. Here, rats were subjected to ICH and NSCs were intracerebrally injected at 3 h after ICH. The profiles of subpopulations of T cells in the brain and peripheral blood were analyzed by flow cytometry. We found that regulatory T (Treg) cells in the brain and peripheral blood were increased, but γδT cells (gamma delta T cells) were decreased, along with increased anti-inflammatory cytokines (IL-4, IL-10 and TGF-β) and decreased pro-inflammatory cytokines (IL-6, and IFN-γ), compared to the vehicle-treated control. Our data suggest that transplanted NSCs protect brain injury after ICH via modulation of Treg and γδT cell infiltration and anti- and pro-inflammatory cytokine release.     

The lethal giant larvae Gene in Tribolium castaneum: Molecular Properties and Roles in Larval and Pupal Development as Revealed by RNA Interference

We identified and characterized the TcLgl gene putatively encoding lethal giant larvae (Lgl) protein from the red flour beetle (Tribolium castaneum). Analyses of developmental stage and tissue-specific expression patterns revealed that TcLgl was constitutively expressed. To examine the role of TcLgl in insect development, RNA interference was performed in early (1-day) larvae, late (20-day) larvae, and early (1-day) pupae. The early larvae injected with double-stranded RNA of TcLgl (dsTcLgl) at 100, 200, and 400 ng/larva failed to pupate, and 100% mortality was achieved within 20 days after the injection or before the pupation. The late larvae injected with dsTcLgl at these doses reduced the pupation rates to only 50.3%, 36.0%, and 18.2%, respectively. The un-pupated larvae gradually died after one week, and visually unaffected pupae failed to emerge into adults and died during the pupal stage. Similarly, when early pupae were injected with dsTcLgl at these doses, the normal eclosion rates were reduced to only 22.5%, 18.0%, and 11.2%, respectively, on day 7 after the injection, and all the adults with abnormal eclosion died in two days after the eclosion. These results indicate that TcLgl plays an essential role in insect development, especially during their metamorphosis.     

关于煤炭机电设备的安装与管理

以煤炭机电设备的安装与管理为探究主题,对煤炭机电设备安装与管理工作的重要性进行了简述,分析了煤炭机电设备安装与管理中存在的问题,并提出了相应策略。     

露天液压钻车变幅机构运动学分析与工作空间研究

针对某型露天液压钻车对变幅机构进行了介绍,首先利用D-H法建立露天液压钻车变幅机构的坐标系,并采用齐次变换法,建立其运动学方程;选取变幅机构特定姿态,验证所得运动学方程的正确性;利用MATLAB进行编程计算,采用伪随机数法得到露天液压钻车变幅机构的可达工作空间、有效工作空间及有效工作范围的相关视图,并进行了三种工作空间的对比。全面系统的提出了露天液压钻车变幅机构运动学分析方法与相关工作空间的概念。     

基于梯度图的快速POCS超分辨率复原算法研究

随着红外成像相关产业的兴起,红外成像技术具有的隐蔽性好、探测范围广、定位精度高、穿透距离远,以及轻质小巧、低耗可靠等优点备受青睐,已成为当前智能化光电探测发展的主流方向。然而,红外弱小目标的图像细节特征少、信噪比低等特点成为红外图像应用的瓶颈,如何提高红外弱小目标成像效果成为目前的研究热点。POCS算法是目前超分辨率复原中应用非常广泛的一种复原算法,但是该算法运算量大,处理时间较长,同时对图像的边缘细节保留能力较差。针对POCS超分辨率复原算法迭代时间较长,无法满足光电探测系统实时性的问题,提出了基于梯度图的快速POCS超分辨率复原算法(GPOCS)。该算法根据图像的梯度分布对图像中的像素点进行分类,采用不同的迭代系数进行计算。改进算法能够较好的保留边缘信息并抑制噪声,进而在保证超分辨率复原性能的基础上大大缩短了运算时间。实验结果表明:GPOCS算法复原结果在背景处噪声得到一定的抑制,整体复原能力优于传统的POCS复原方法。该算法能够有效地保留边缘细节,同时处理时间小于传统的POCS复原方法,减少了1个数量级已经是接近实时。GPOCS算法能够自适应的选取迭代步长,较好的保留边缘信息并抑制噪声,进而在保证超分辨率复原性能的基础上大大缩短了运算时间,虽然不能满足实时性的要求,但是也已经是接近实时。