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1.
采用Ansys软件对厢式压滤机滤板受力和挠度形变进行数值模拟,着重分析凸台支柱数量的影响。基于变分法滤板挠度计算找出滤室边长尺寸与滤板设计厚度的关系,建立厢式压滤机滤板总体积、滤板组总长度与滤室边长的函数关系,以此对滤板结构进行优化设计。经优化后的滤板与1250型滤板相比,污泥脱水的工作效率得到明显提高——在整机滤室容积不变的情况下,虽滤板耗材增加了7.51%,但过滤面积增加了近50%,继而在泥饼达到同等含水率时压滤时间缩短了36.9%。  相似文献   

2.
疏松砂岩储层渗透率变化范围大,压裂液滤失表现出较大差异。针对疏松砂岩储层压裂液滤失难以估量的问题,开展静态滤失实验研究不同胍胶浓度压裂液在不同压差环境下的滤失规律,确定滤失系数与压差关系。首先开展滤纸滤失实验,研究压裂液滤失对滤失压差的依赖性,随后针对疏松砂岩渗透率变化范围大的特点开展岩板滤失实验,探索岩板渗透率对压裂液滤失特性的影响。结果表明:压裂液的滤饼滤失系数与压差的幂指数成正比,与胶粉浓度的倒数平方根成正比。  相似文献   

3.
《玻璃纤维》2007,(5):11-11
本发明涉及用于水处理工程对废水内固体和液体进行分离的设备,具体为一种玻璃纤维海水专用砂滤器。该装置包括进排水管、石英砂滤层及反冲洗排污管,石英砂滤层安装于罐体内,所述石英砂滤层由滤水帽和滤水帽托板构成,石英砂置于安装有滤水帽的滤水帽托板上,滤水帽托板将罐体分成上下两个腔室,进水管和排水管穿过罐体侧壁,分别与滤水帽托板上、下相通,反冲洗排污管与滤水帽托板下部相通。  相似文献   

4.
油层水力压裂是油气井增产、注水井增注的一项重要工艺措施。压裂施工的成功与否主要取决于所用的压裂液。而压裂液的滤失是影响压裂施工效果的重要因素之一。所以本文首先对压裂液滤失的危害进行了分析,综述了压裂液的滤失机理、影响因素。同时对降滤失技术进行了研究:目前常用的降滤失技术有提高压裂液粘度,添加压裂液降滤失剂和液氮降滤失技术等。最后对降滤失技术的发展进行了展望。  相似文献   

5.
压裂液降滤失技术研究   总被引:1,自引:0,他引:1  
油层水力压裂是油气井增产、注水井增注的一项重要工艺措施。压裂施工的成功与否主要取决于所用的压裂液。而压裂液的滤失是影响压裂施工效果的重要因素之一。所以本文首先对压裂液滤失的危害进行了分析,综述了压裂液的滤失机理、影响因素,同时对降滤失技术进行了研究,目前常用的降滤失技术能提高压裂液粘度,添加压裂液降滤失剂和液氮降滤失技术等。最后对降滤失技术的发展进行了展望。  相似文献   

6.
采用沸石和砾石构建生态滤坝,研究不同组配方式下生态滤坝的污染物去除效果,同时将铁碳微电解技术引入生态滤坝,研究铁碳生态滤坝对微污染河水水质净化效果。结果表明,混合滤坝的NH3-N和TN的平均去除率比分层滤坝分别高9.75个和8.01个百分点,说明基质混合生态滤坝的污染物去除效果更好。铁碳生态滤坝的COD、NH3-N、NO2--N、TN的平均去除率分别比混合滤坝提高18.68个、4.17个、15.56个和8.99个百分点,说明添加铁碳可以增强生态滤坝对COD和TN等污染物的去除能力。通过微生物群落结构及多样性分析,铁碳滤坝微生物群落多样性较高,优势菌为假单胞菌属和狭义梭菌属。  相似文献   

7.
综述了国内外新型淀粉基钻井液降滤失剂的合成工艺,并分析了淀粉基降滤失剂的降滤失机理。研究结果表明,近期发展起来的淀粉基降滤失剂的合成工艺有半干法、微波辅助干法、微乳化法、双水相法等。淀粉基降滤失剂降滤失机理分为增黏机理、吸附-水化机理、捕集机理、物理堵塞机理等4种。研究结果可为开发淀粉基降滤失剂绿色制备工艺,以及研发新型淀粉基降滤失剂提供理论依据。  相似文献   

8.
《广东化工》2021,48(15)
塑料滤毒罐各塑料件间的连接是通过超声波焊接工艺完成的装配,而塑料滤毒罐在使用过程中会出现焊口开裂的问题,即滤烟层与滤毒层焊口处。分析其原因,并形成塑料滤毒罐可靠性改进工作路线,通过运用正交试验分析方法,确定最佳的焊接工艺参数,进行环境适应性试验验证,来提高塑料滤毒罐超声波焊接的焊接质量,提升塑料滤毒罐使用过程中的可靠性。  相似文献   

9.
为了研究乳化剂对滤失量的影响,从静滤失方程出发,利用达西定律描述钻井液通过泥饼和滤纸的滤失速率,建立了油基钻井液的单因素和双因素滤失模型,并进行了对比分析。然后通过室内实验进行论证,表明乳化剂类型不同,配制的钻井液体系的滤失量不同,乳化率高的乳化剂对应的滤失量小;同时,乳化剂加量对体系的滤失量也有影响。  相似文献   

10.
在采油过程中,钻井液起到重要的作用,但钻井液的滤失性能是钻井液的主要性能,对稳固井壁起到重要的作用,本文主要从静滤失、动滤失、瞬时滤失等三个方面综述了井内钻井液的滤失性能。  相似文献   

11.
During infections, the host redistributes iron in order to starve pathogens from this nutrient. Several proteins are involved in iron absorption, transport, and storage. Ferritin is the most important iron storage protein. It is composed of variable proportions of two peptides, the L- and H-ferritins (FTL and FTH). We previously showed that macrophages increase their expression of FTH1 when they are infected in vitro with Mycobacterium avium, without a significant increase in FTL. In this work, we investigated the role of macrophage FTH1 in M. avium infection in vivo. We found that mice deficient in FTH1 in myeloid cells are more resistant to M. avium infection, presenting lower bacterial loads and lower levels of proinflammatory cytokines than wild-type littermates, due to the lower levels of available iron in the tissues. Importantly, we also found that FTH1 produced by myeloid cells in response to infection may be found in circulation and that it plays a key role in iron redistribution. Specifically, in the absence of FTH1 in myeloid cells, increased expression of ferroportin is observed in liver granulomas and increased iron accumulation occurs in hepatocytes. These results highlight the importance of FTH1 expression in myeloid cells for iron redistribution during infection.  相似文献   

12.
The first step in the process of vegetable oil refining is degumming, in which phospholipids and mucilaginous gums are removed that otherwise result in a low-grade oil. A membrane process is remarkably simple yet potentially offers many advantages in degumming. Studies were conducted on surfactant-aided membrane degumming with soybean and rapeseed oils in a magnetically stirred flat membrane batch cell with different types of microfiltration membranes. The reduction of phospholipids in soybean oil was in the range of 85.8–92.8% during the membrane process. The phosphorus content of membrane permeates of soybean oil was in the range of 20–58 mg/kg. Crude rapeseed oil contained higher amount of nonhydratable phospholipids and hence resulted in lower reduction in phospholipids, in the range of 66.4–83.2%. Addition of hydratable phospholipids could improve the efficiency of degumming in the membrane process without using any electrolyte, resulting in improvement of quality as well as quantity of the phospholipids.  相似文献   

13.
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.  相似文献   

14.
Sato M  Kawata Y  Erami K  Ikeda I  Imaizumi K 《Lipids》2008,43(2):125-131
Liver and intestine are major sites of apo A-I synthesis in mammals. ABCAI is reported to be involved in the secretion of nascent HDL from cultured intestinal cells. However, whether ABCA1 participates in the secretion of nascent HDL from the intestine has not been assessed directly in vivo. This study examined the effect of a synthetic LXR-agonist “TO” on the lymphatic transport of HDL in thoracic duct-cannulated rats. The feeding of a TO-containing diet resulted in an increased transport of cholesterol and apo A-I in the lymph d > 1.063 g/ml lipoprotein fraction than did the feeding of a control diet without TO. The transport of cholesterol in whole lymph was lower, whereas the transport of apo A-I was higher, in the TO group. The abundance of mRNAs for ABCAI and apo A-I in the intestine was increased in the TO group. Furthermore, although the TO-containing diet reportedly increased the serum HDL concentration in intact mice and rats, no such effect was observed in the cannulated rats. The LXR agonist stimulated in vivo the synthesis of nascent HDL by increasing reciprocally the mRNA for ABCAI and apo A-I in the intestine, thereby contributing to an increase in the circulating HDL.  相似文献   

15.
We examined several environmental and developmental influences on trypsin inhibitor (TI) activity in leaves of young Brassica napus seedlings in a series of greenhouse experiments. In seedlings of B. napus cv. Westar, TI activity is constitutively present and exhibits a rise then fall through time in the first true leaves of young plants. TI activity is induced by wounding in the first true leaves, but the degree of induction is relatively insensitive to the degree of wounding over a gradient of 5–15% of leaf area damage. TI activity is enhanced in first true leaves of plants in which the cotyledons have been wounded relative to plants in which the cotyledons have not been wounded. TI activity is also enhanced in the second true leaves on plants in which the first true leaves have been wounded. The degree of systemic induction in second true leaves declines additively with plant age, but local induction in the first true leaves is not affected by age. In B. napus cv. Gido, TI activity is constitutively present but is not locally wound-inducible in first true leaves of young plants exposed to the same wounding gradient as cv. Westar. In unwounded plants at the six-leaf stage, TI activity is higher in second true leaves than in fifth true leaves, indicating that TI activity is developmentally regulated in this cultivar.  相似文献   

16.
The stability of sodium hypochlorite in the presence of surfactants   总被引:2,自引:0,他引:2  
Studies were made on the stability of NaOCl at 40°C in the presence of sodium alkanesulfonate or alkylarenesulfonate anionic surfactants, and in the presence of a nonionic surfactant,N-octylpyrrolidinone. The results were compared with NaOCl stability in the absence of additives and in the presence of nonsurfactant short-chain sodium alkylbenzenesulfonates. The data indicated that the rate of NaOCl loss is greatly dependent upon the pH of the solution, even at alkaline pHs. At initial pHs below 11, in the absence of additive, there is significant disproportionation of OCl to ClO 3 , accompanied by decrease in the pH of the solution, within a period of several days. Even at an initial pH of 11.3, in the presence of the surfactants investigated, there is significant disproportionation of OCl and decrease in the pH of the solution in the first several days. When the initial pH of the solution is 13.5, there is no significant decrease in pH of the solution for at least two months in the presence of the surfactants studied. NaOCl stability in the presence of surfactant decreases in the order: sodium linear alkanesulfonate > sodium linear alkyldiphenylethersulfonate > sodium linear alkylbenzenesulfonate >>N-octylpyrrolidinone. Stability was greater in the presence of linear alkylarenesulfonates than in the presence of branched alkylarenesulfonates. It is suggested that the differences in stability observed are due to the greater ease of oxidation of tertiary carbon atoms compared to primary or secondary atoms.  相似文献   

17.
A relatively large wet material was immersed in a fluidized bed of hygroscopic porous particle (silica gel beads) under reduced pressure. And then the drying characteristics were compared with those in the case of inert particle (glass beads). The comparison of drying characteristics is performed experimentally and theoretically. In calculation, the water transfer from the sample to the fluidized bed was considered. The calculation results are in good agreement with the experimental data. The effects of the operational conditions (the pressure in the drying chamber and the temperature of the drying gas) on the drying characteristics were also examined in both fluidizing particles.The drying finishes earlier in the case of hygroscopic porous particle than in the case of inert particle regardless of pressure in the drying chamber, since the water transfer from the sample facilitates the drying in the case of hygroscopic porous particles. The temperature decrement in drying appears in the case of inert particle. This phenomenon is also observed in the case of hygroscopic porous particle, but the decrement degree of the temperature is much smaller than that in the case of inert particle. The difference of the minimum temperature in the sample in drying between the cases of hygroscopic porous particle and inert particle is very slight for different pressures in the drying chamber.  相似文献   

18.
王彦  左宁  姜媛媛  陈芳媛 《化工进展》2020,39(4):1539-1549
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。  相似文献   

19.
Endometrial cancer (EC) is the fourth most common cancer in women in developed countries. Although it is usually diagnosed in postmenopausal women, its incidence has increased in young women, as well in recent decades, with an estimated rate of 4% in those under 40 years of age. Factors involved in this increase, particularly in resource-rich countries, include delayed childbearing and the rise in obesity. The new molecular classification of EC should help to personalize treatment, through appropriate candidate selection. With the currently available evidence, the use of oral progestin either alone or in combination with other drugs such as metformin, levonorgestrel-releasing intrauterine devices and hysteroscopic resection, seems to be feasible and safe in women with early-stage EC limited to the endometrium. However, there is a lack of high-quality evidence of the efficacy and safety of conservative management in EC. Randomized clinical trials in younger women and obese patients are currently underway.  相似文献   

20.
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.  相似文献   

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