水力旋流器流场特征和分级分离性能研究综述

水力旋流器利用颗粒-颗粒或颗粒-流体在旋流流场中运动行为差异实现分级分离过程,被广泛地应用于化工、冶金、矿物加工和环保等行业。在实际运行中,由于操作条件不合理或设备结构条件限制,使颗粒分级或固液分离性能无法满足应用需求,本文分析了水力旋流器的流场特征,并总结了影响旋流器分离性能的关键因素。水力旋流器内部呈现复杂的多相流场,颗粒性质、料液性质、进料条件等操作参数和旋流器的几何结构会影响水力旋流器的分离性能,实际应用中可以通过优化运行条件和旋流器的几何结构,提高旋流器的分级分离性能。     

CCФ380水力旋流器的应用及分级效果评定

对CCΦ380水力旋流器的分级粒度和处理能力进行了验证 ,介绍了影响水力旋流器运行和分级效果的主要因素 ,对水力旋流器的实际应用情况作了比较全面的分析 ,并对其分级效果进行了评定     

CCΦ380水力旋流器的应用及分级效果评定

对CCΦ380水力旋流器的分级粒度和处理能力进行了验证，介绍了影响水力旋流器运行和分级效果的主要因素，对水力旋流器的实际应用情况作了比较全面的分析，并对其分级效果进行了评定。     

操作参数对水力旋流器壁面磨损的影响研究

水力旋流器是利用离心力场加速其内部颗粒沉降和强化分离过程的分离设备。水力旋流器内的介质在离心力场作用下做强烈的旋转运动,对水力旋流器壁面造成冲击和摩擦,因此磨损问题是水力旋流器最主要的失效形式。针对水力旋流器壁面出现的严重磨损问题,采用数值模拟与实验相结合的方法,研究操作参数对水力旋流器壁面磨损规律。利用Fluent求解其内部流场和固体颗粒的运动特性。探究水力旋流器的操作参数进口速度和颗粒粒径对壁面磨损的影响规律。搭建了一套水力旋流器壁面磨损实验装置进行磨损实验,与数值模拟的结果作比较,实验规律与数值模拟相符。     

水力旋流器结构参数对其性能的影响

水力旋流器结构简单,广泛地应用于各工业部门,影响水力旋流器性能的因素很多,但结构参数是影响水力旋流器性能的关键因素.本文对水力旋流器结构参数变化对其处理能力、分流比、浓缩倍数等影响作了全面的试验研究.为水力旋流器的设计、制造提供参考.     

用于超细分级的水力旋流器的研究

介绍了用于细粒煤泥分级的水力旋流器的工作原理;分析了旋流器内流体质点的切向速度、径向速度和轴向速度的分布规律及在分离过程中的作用;同时,给出了水力旋流器结构参数的设计标准。     

水力旋流器在中海油的应用研究

介绍水力旋流器的工作原理和基本结构,以及在中海油的应用状况,分析水力旋流器工作中的影响因素及其在海上油田污水处理系统中出现的若干问题,并展望水力旋流器在含污水处理系统中及其他工艺处理系统中的应用前景。     

两相流旋流器在晋宁磷矿擦洗厂的应用研究

通过对晋宁磷矿擦洗厂三段开路流程第三段旋流器的改造,对比了Ф125三相流水力旋流器与新型Ф75两相流旋流器在磷矿石洗选中的实际应用效果,说明两相流旋流器回收磷矿细粒级产品的效果优于普通三相流旋流器。     

充气水力雄流器内矿化气泡运动行为的研究

本文对充气水力旋流器内的矿化气泡（特指矿粒与气泡聚合体的总称）从形成处到进入泡沫柱区这一过程行为进行了全面的研究，采用快速摄像分析法测定了气泡的运动行为，从压力梯度的角度着手研究了矿化气泡运动过程中的推动力，还从理论上探讨了矿粒大小及离心力强度对矿化气泡运动行为的影响等。本研究结果使用充气水力旋流器内矿化气泡的运动行为得到了较为系统的描述，从而为揭示充气水力旋流器内的分选过程行为作出了重要贡献。     

充气水力旋流器内矿化气泡运行行为的研究

本文对充气水力旋流器内的矿化气泡（特指矿粒与气泡聚合体的总体）从形成处到进入泡沫柱区这一过程行为进行了全面的研究，采用快速摄像分析法测定了气泡的运动行为，从压力梯度的角度着手研究了矿化气泡运动过程中的推动力，还从理论上探讨了矿粒大小及离心力强度对矿化气泡运动行为的影响等，本研究结果使用充气水力旋流器内矿化气泡的运动行为得到了较为系统的描述，从而为揭示充气水力旋流器内的分选过程行为作出了重要贡献。     

泰乐菌素在提取工艺中溶液中的稳定性研究

为探讨泰乐菌素在提取工艺中溶液中的稳定性,取提取工艺中不同环节的泰乐菌素溶液,采用高效液相色谱法测定在一定时间内检测泰乐菌素的含量,观察不同环节的泰乐菌素溶液的降解情况。结果显示,在提取工艺中不同环节的泰乐菌素溶液,均较稳定,结果证明,提取工艺中不同环节的泰乐菌素溶液稳定,基本上不降解。     

污泥生物炭中氮硫行为及环境效应研究进展

污泥生物炭中氮硫元素含量高,其氮硫行为和环境效应对全球气候变化的影响不容忽视。以往的研究中,研究者往往以富碳生物炭作为主要研究对象,关注碳对全球气候变化的行为和功效,而对氮硫元素的作用关注不够。本文从原始污泥基本性质到其热解过程,再到生物炭的老化,逐步对污泥生物炭整个生命周期内氮硫的行为及其环境效应研究进行综述,并对未来应注重开展的研究方向进行展望,为生物炭中氮硫元素固定、释放及与之关联的环境效应和温室气体排放控制研究提供理论基础。分析表明,污泥中氮元素含量普遍高于硫元素,且热解过程中氮比硫更容易转移至气相产物。氮硫元素随热解温度的增加,在三相产物中的分配都是炭中持续减少,油中先增后减,气中一直增加。高温（＞800℃）条件下,气相中的氮含量高于固相,而硫元素则仍然主要存在于固相中。污泥生物炭老化及其环境效应研究表明,污泥生物炭氮硫元素与土壤的相互作用及其温室效应问题在今后的研究中应引起重视。     

The Effects of Immunosuppressive Treatment during Pregnancy on the Levels of Potassium,Iron, Chromium,Zinc, Aluminum,Sodium and Molybdenum in Hard Tissues of Female Rats and Their Offspring

The ideal immunosuppressive regimen should provide for excellent immunosuppression with no side effects. Yet, current immunosuppressive therapy regimens commonly used in clinical applications fail to meet this criterion. One of the complications caused by immunosuppressive drugs is mineralization disorders in hard tissues. In this study, we evaluated the effects of three immunosuppressive therapies used after transplantation on the levels of potassium, iron, chromium, zinc, aluminum, sodium and molybdenum in the bones and teeth of female rats and their offspring. The study was conducted on 32 female Wistar rats, subjected to immunosuppressive regimens (cyclosporine A, mycophenolate mofetil and prednisone; tacrolimus, mycophenolate mofetil and prednisone; and cyclosporine A, everolimus and prednisone). The hard tissues of rats were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES, ICAP 7400 Duo, Thermo Scientific) equipped with a concentric nebulizer and a cyclonic spray chamber. All the immunosuppressive regimens included in the study affected the concentrations of the studied minerals in hard tissues of female rats and their offspring. The therapy based on cyclosporine A, everolimus and prednisone led to a decline in the levels of iron in bone, zinc in teeth, and molybdenum in the bone and teeth of mothers, while in the offspring, it caused a decline of bone potassium, with a decrease in iron and increase of molybdenum in teeth. Moreover, the regimen caused an increase in aluminum and chromium in the teeth and aluminum in the bones of the offspring, and consequently, it seems to be the therapy with the most negative impact on the mineral metabolism in hard tissues.     

Sp7 Transgenic Mice with a Markedly Impaired Lacunocanalicular Network Induced Sost and Reduced Bone Mass by Unloading

The relationship of lacunocanalicular network structure and mechanoresponse has not been well studied. The lacunocanalicular structures differed in the compression and tension sides, in the regions, and in genders in wild-type femoral cortical bone. The overexpression of Sp7 in osteoblasts resulted in thin and porous cortical bone with increased osteoclasts and apoptotic osteocytes, and the number of canaliculi was half of that in the wild-type mice, leading to a markedly impaired lacunocanalicular network. To investigate the response to unloading, we performed tail suspension. Unloading reduced trabecular and cortical bone in the Sp7 transgenic mice due to reduced bone formation. Sost-positive osteocytes increased by unloading on the compression side, but not on the tension side of cortical bone in the wild-type femurs. However, these differential responses were lost in the Sp7 transgenic femurs. Serum Sost increased in the Sp7 transgenic mice, but not in the wild-type mice. Unloading reduced the Col1a1 and Bglap/Bglap2 expression in the Sp7 transgenic mice but not the wild-type mice. Thus, Sp7 transgenic mice with the impaired lacunocanalicular network induced Sost expression by unloading but lost the differential regulation in the compression and tension sides, and the mice failed to restore bone formation during unloading, implicating the relationship of lacunocanalicular network structure and the regulation of bone formation in mechanoresponse.     

220MW热电联产锅炉中痕量元素的迁移及分布特性

本实验在北京某220 MW热电联产锅炉上进行。采用承重撞击器系统对该锅炉SCR前、ESP前以及FGD前的颗粒物进行采集,研究了痕量元素在烟道沿程上的迁移特性,另外,还给出了痕量元素在各固体燃烧产物中的分布。结果表明：ESP前的颗粒物上As、Cd、Cr和Pb的浓度明显高于SCR前的浓度;在从SCR到ESP的过程中,As、Cd、Cr、Pb从气态迁移到固态的质量分别占到了原煤中总质量的26 %、16 %、12 %和11 %;从ESP到FGD的过程中,颗粒物上As与Cd的浓度有略微增加,而Cr和Pb的浓度几乎不变;Mn在三个采样点的浓度几乎一致;绝大部分痕量元素存在于ESP捕获的飞灰中,在ESP出口处,As、Cd、Cr、Pb在<10 μm的四个粒径段上的质量随着粒径的减小而增大,而Mn的质量分布与颗粒物质量分布类似。     

Possible Role of Crystal-Bearing Cells in Tomato Fertility and Formation of Seedless Fruits

Crystal-bearing cells or idioblasts, which deposit calcium oxalate, are located in various tissues and organs of many plant species. The functional significance of their formation is currently unclear. Idioblasts in the leaf parenchyma and the development of crystal-bearing cells in the anther tissues of transgenic tomato plants (Solanum lycopersicon L.), expressing the heterologous FeSOD gene and which showed a decrease in fertility, were studied by transmission and scanning electron microscopy. The amount of calcium oxalate crystals was found to increase significantly in the transgenic plants compared to the wild type (WT) ones in idioblasts and crystal-bearing cells of the upper part of the anther. At the same time, changes in the size and shape of the crystals and their location in anther organs were noted. It seems that the interruption in the break of the anther stomium in transgenic plants was associated with the formation and cell death regulation of a specialized group of crystal-bearing cells. This disturbance caused an increase in the pool of these cells and their localization in the upper part of the anther, where rupture is initiated. Perturbations were also noted in the lower part of the anther in transgenic plants, where the amount of calcium oxalate crystals in crystal-bearing cells was reduced that was accompanied by disturbances in the morphology of pollen grains. Thus, the induction of the formation of crystal-bearing cells and calcium oxalate crystals can have multidirectional effects, contributing to the regulation of oxalate metabolism in the generative and vegetative organs and preventing fertility when the ROS balance changes, in particular, during oxidative stresses accompanying most abiotic and biotic environmental factors.     

Ion-doped hydroxyapatite: An impasse or the road to follow?

Doping hydroxyapatite (HAp) with foreign ions has been increasing in popularity as a chemical approach to augment the existing and impart new properties to it. However, it is uncertain whether this approach can elicit properties strong enough to make HAp competitive for commercial applications in biomedicine and elsewhere. In particular, material properties, such as grain size, morphology, surface charge, porosity, topology and others may prove to be more effective in controlling properties of HAp than the dopant choice and concentration. This study tackles this question through a meta-analysis of the dependence of selected materials properties on dopant concentrations reported across the literature, showing that doping is a convenient way of controlling some, but not all properties in HAp and should be implemented ideally in combination with other structural and compositional factors of influence. This meta-analysis is coupled to a bibliographic analysis of the evolution of trends in terms of the type, frequency and concurrency of dopants in HAp, covering the entire Periodic Table, all 72 elements incorporated into HAp so far and the 1990 – 2019 period split into successive lustra. The study demonstrates a continuously ascending trend in popularity of certain elements, such as Sr, Ce and Se, and a continuously declining trend of others in the past two decades, including F, Y, I, Ti and most lanthanides. For the fourth period transition metals a trend of constancy was observed and for yet other elements, including Ag and Mg, a period of ascent was succeeded by a steady decline, the onset of which coincided in the case of Ag with the peak in the airing of the concerns over its cytotoxicity by the scientific community. Reasons for these trends with respect to most elements are explained and connected with trends governing broader realms of materials science. It is shown that the choice of ions as dopants in HAp is largely driven by broader trends in materials science, rendering the doped HAp a mirror to view these existing and past trends in. Theoretically, by following the historic progression of these trends, a gaze in this mirror could assist in extrapolation of future trends, which normally come at the cost extinguishing some of the existing ones. This immersion in more general developments in materials science opened the path toward drawing connections between the bibliographically assessed geopolitical trends in doped HAp and in broader aspects of the scientific community, including the growing gap between the rich and the poor pervading it. The analysis reported here is conceptually novel and could be applied to numerous other materials.     

On the Need to Distinguish between Insulin-Normal and Insulin-Resistant Patients in Testosterone Therapy

Male hypogonadism is a disorder characterized by low levels of the hormone testosterone and patients may also have insulin sensitivity (IS) or insulin resistance (IR), such that they show different clinical complications and different metabolic pathways. In this review, we compare metabonomic differences observed between these two groups before and after testosterone therapy (TRT) in order to obtain information on whether the two hormones testosterone and insulin are synergistic or antagonistic. IS hypogonadism uses glucose as the main biofuel, while IR activates gluconeogenesis by the degradation of branched-chain amino acids. The Krebs (TCA) cycle is active in IS but connected with glutaminolysis, while in IR the TCA cycle stops at citrate, which is used for lipogenesis. In both cases, the utilization of fatty acids for energy (β-oxidation) is hampered by lower amounts of acetylcarnitine, although it is favored by the absence of insulin in IR. Increased free fatty acids (FFAs) are free in the blood in IS, while they are partially incorporated in triglycerides in IR. Thus, upon TRT, the utilization of glucose is increased more in IS than in IR, revealing that in IR there is a switch from preferential glucose oxidation to lipid oxidation. However, in both cases, a high production of lactate and acetyl-CoA is the final result, with these levels being much higher in IR. Lactate is used in IS in the glucose–lactate cycle between the liver and muscle to produce energy, while in IR lactate and acetyl-CoA are biotransformed into ketone bodies, resulting in ketonuria. In conclusion, the restoration of testosterone values in hypogonadism gives better results in IS than in IR patients: in IS, TRT restores most of the metabolic pathways, while in IR TRT impairs insulin, and when insulin is inactive TRT activates an ancestral molecular mechanism to produce energy. This evidence supports the hypothesis that, over time, hypogonadism switches from IS to IR, and in the latter case most of the insulin-related metabolisms are not reactivated, at least within 60 days of TRT. However, testosterone therapy in both IS and IR might be of benefit given supplementation with metabolites that are not completely restored upon TRT, in order to help restore physiological metabolisms. This review underlines the importance of using a systems biology approach to shed light on the molecular mechanisms of related biochemical pathways involving insulin and testosterone.     

Streptozotocin-Induced Diabetes Causes Changes in Serotonin-Positive Neurons in the Small Intestine in Pig Model

Serotonin (5-hydroxytryptamine or 5-HT) is an important neurotransmitter of the central and peripheral nervous systems, predominantly secreted in the gastrointestinal tract, especially in the gut. 5-HT is a crucial enteric signaling molecule and is well known for playing a key role in sensory-motor and secretory functions in the gut. Gastroenteropathy is one of the most clinical problems in diabetic patients with frequent episodes of hyperglycemia. Changes in 5-HT expression may mediate gastrointestinal tract disturbances seen in diabetes, such as nausea and diarrhea. Based on the double immunohistochemical staining, this study determined the variability in the population of 5-HT-positive neurons in the porcine small intestinal enteric neurons in the course of streptozotocin-induced diabetes. The results show changes in the number of 5-HT-positive neurons in the examined intestinal sections. The greatest changes were observed in the jejunum, particularly within the myenteric plexus. In the ileum, both de novo 5-HT synthesis in the inner submucosal plexus neurons and an increase in the number of neurons in the outer submucosal plexus were noted. The changes observed in the duodenum were also increasing in nature. The results of the current study confirm the previous observations concerning the involvement of 5-HT in inflammatory processes, and an increase in the number of 5-HT -positive neurons may also be a result of increased concentration of the 5-HT in the gastrointestinal tract wall and affects the motor and secretory processes, which are particularly intense in the small intestines.     

Gangliosides in Podocyte Biology and Disease

Gangliosides constitute a subgroup of glycosphingolipids characterized by the presence of sialic acid residues in their structure. As constituents of cellular membranes, in particular of raft microdomains, they exert multiple functions, some of them capital in cell homeostasis. Their presence in cells is tightly regulated by a balanced expression and function of the enzymes responsible for their biosynthesis, ganglioside synthases, and their degradation, glycosidases. The dysregulation of their abundance results in rare and common diseases. In this review, we make a point on the relevance of gangliosides and some of their metabolic precursors, such as ceramides, in the function of podocytes, the main cellular component of the glomerular filtration barrier, as well as their implications in podocytopathies. The results presented in this review suggest the pertinence of clinical lipidomic studies targeting these metabolites.