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1.
活性炭吸附处理含铬电镀废水的研究   总被引:1,自引:0,他引:1  
利用活性炭吸附处理含铬电镀废水,对处理的工艺条件进行系统研究,确定了吸附最佳pH 值、吸附平衡时间、吸附等温方程式及穿透曲线,并对活性炭再生效果进行比较。结果表明,利用活性炭吸附处理含铬电镀废水,具有处理效果好,操作简单,再生容易等优点  相似文献   

2.
活性炭吸附处理含铬电镀废水的研究   总被引:8,自引:0,他引:8  
利用活性炭吸附处理含铬电镀废水,对处理的工艺条件进行系统研究,确定了吸附最佳pH值,吸附平衡时间,吸附等温方程式及穿透曲线,并对活性炭再生效果进行比较。结果表明,利用活性吸附处理含铬电镀废水的具有处理效果好,操作简单,再生容易等优点。  相似文献   

3.
粉煤灰多孔陶粒在含铬废水处理中的应用研究   总被引:3,自引:0,他引:3  
邹杰文  李超 《广东化工》2009,36(6):144-145
研究采用电厂的粉煤灰为主要原料制备多孔陶粒,用多孔陶粒作吸附剂处理含铬废水时,等温吸附实验表明,多孔陶粒吸附废水中的铬的等温方程基本符合Langmiur等温方程式,在pH为酸性时对铬的去除率较高.  相似文献   

4.
活性炭对含铬废水的吸附处理研究   总被引:19,自引:0,他引:19  
研究了活性炭吸附处理实验室模拟含铬废水。实验结果表明,当活性炭用量为1 g,废水pH=4~5,吸附接触时间大于1 h,活性炭与铬含量比值大于5 mg Cr6+/g活性炭时,处理效果可达99%以上;吸附符合Freund lich等温模式,吸附等温方程式为logq=0.7780+0.9716 logc,以物理吸附为主;吸附穿透体积为25 mL,活性炭吸附Cr6+的工作吸附容量为14.59 mg Cr6+/g活性炭,工作饱和吸附容量为803.41 mg Cr6+/g活性炭。  相似文献   

5.
《广州化工》2021,49(8)
含铬废水污染通过食物链或环境危害人们的健康,含铬废水无害化处理及污染控制至关重要。介绍了含铬废水中铬处理的萃取法、生物还原法、离子交换法、化学还原法、光催化、吸附法等的进展以及优缺点,铬吸附量测定方法近期进展。含铬废水中的铬吸附过程热力学分析对吸附处理效率的提高有帮助。利用铬吸附等温线有关文献,综述有关炭材料吸附处理铬以及铬吸附数据的热力学研究现状。  相似文献   

6.
焦粉基活性炭处理含铬废水的研究   总被引:1,自引:0,他引:1  
用焦粉基活性炭吸附处理含铬废水,考察了pH值、吸附时间、Cr(Ⅵ)浓度、焦粉基活性炭加入量等因素对含铬废水去除率的影响.结果表明,用焦粉活性炭吸附处理含铬废水,处理效果明显,成本低、可再生.  相似文献   

7.
底泥对含铬废水的吸附处理研究   总被引:3,自引:0,他引:3  
通过底泥吸附处理模拟含铬(Cr^6+)废水,探讨了废水酸度、吸附时间、底泥用量、粒径对铬(Cr^6+)吸附效果的影响。静态实验结果表明:在废水pH为10,用3.0g底泥吸附处理浓度为100mg/L的含铬废水40mL,吸附接触时间5h时,其处理效果最佳。动态实验结果表明:不同粒径底泥的最终吸附效果相差不明显;粒径对废水的流速影响较大,细粒径底泥的流速缓慢,处理所需时间长。利用底泥吸附处理含铬(Cr^6+)废水,去除率能达到95%以上。  相似文献   

8.
李晓颖 《广东化工》2012,39(16):133-134
文章对改性粉煤灰处理含铬(VI)废水进行了研究。通过实验考察了改性粉煤灰加入量、吸附时间、吸附温度和废水的pH对废水中铬(VI)去除率的影响。实验结果表明,改性粉煤灰处理含铬(Ⅵ)废水的最佳工艺条件为:改性粉煤灰加入量为1.5g,吸附时间为10min,吸附温度为25℃,废水的pH为6.0。在此条件下可使50mL模拟含铬废水中铬(VI)浓度由10mg/L降到0.47mg/L,铬(VI)去除率达95%以上,达到了国家《污水综合排放标准》。  相似文献   

9.
离子交换法及吸附法处理含铬废水的研究进展   总被引:14,自引:1,他引:13  
通过对目前含铬废水不同处理方法的比较,认为离子交换法及吸附法是效果较佳的处理方法.在查阅相关文献的基础上,总结了国内外近年来离子交换法及吸附法用于处理含铬废水的研究进展,并针对离子交换法及吸附法在处理含铬废水方面的应用提出了今后发展应加强研究的范围和重点.  相似文献   

10.
用磺化褐煤处理含铬(Ⅵ)废水的研究   总被引:2,自引:0,他引:2  
在静态条件下,对以褐煤为原料制备的磺化褐煤处理含铬(Ⅵ)废水进行了研究。研究了溶液pH值、吸附时间、吸附温度、磺化煤的用量、Cr(Ⅵ)起始浓度等因素对磺化褐煤吸附Cr(Ⅵ)的影响,确定了磺化褐煤处理含铬(Ⅵ)废水的最佳条件:溶液的pH为2.0,Cr(Ⅵ)起始质量浓度为40mg/L,吸附温度为70℃,吸附时间为3h,磺化煤用量为80mg,Cr(Ⅵ)去除率达98%以上。同时探讨了磺化褐煤处理含铬(Ⅵ)废水的反应机理。  相似文献   

11.
12.
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   

13.
This study aimed to describe glutathione peroxidase 4 (GPx4) in rat oocytes, preimplantation embryos, and female genital organs. After copulation, Sprague Dawley female rats were euthanized with anesthetic on the first (D1), third (D3), and fifth days of pregnancy (D5). Ovaries, oviducts, and uterine horns were removed, and oocytes and preimplantation embryos were obtained. Immunohistochemical, immunofluorescent, and Western blot methods were employed. Using immunofluorescence, we detected GPx4 in both the oocytes and preimplantation embryos. Whereas in the oocytes, GPx4 was homogeneously diffused, in the blastomeres, granules were formed, and in the blastocysts, even clusters were present mainly around the cell nuclei. Employing immunohistochemistry, we detected GPx4 inside the ovary in the corpus luteum, stroma, follicles, and blood vessels. In the oviduct, the enzyme was present in the epithelium, stroma, blood vessels, and smooth muscles. In the uterus, GPx4 was found in the endometrium, myometrium, blood vessels, and stroma. Moreover, we observed GPx4 positive granules in the uterine gland epithelium on D1 and D3 and cytoplasm of fibroblasts forming in the decidua on D5. Western blot showed the highest GPx4 levels in the uterus and the lowest levels in the ovary. Our results show that the GPx4 is necessary as early as in the preimplantation development of a new individual because we detected it in an unfertilized oocyte in a blastocyst and not only after implantation, as was previously thought.  相似文献   

14.
Separation and purification techniques are applied in many important fields, such as in the medical, chemical, metallurgical, environmental, and pharmaceutical industries. Recent advances in separation science and the urgent need for highly selective purification have necessitated a rapid progress with respect to the reagents, chemicals, and surfactants used in separation processes to attain a high efficiency and selectivity. Polymeric materials have attracted considerable interest, and they have been widely used as extractants, catalysts, and modifiers, in separation and purification processes. This review outlines the recent advances in the use of novel polymers, natural and synthetic, in different separation and purification techniques. Various separation techniques such as chromatography, crystallization, precipitation, distillation, electrophoresis, filtration, and mineral processing methods are discussed, and the polymers used in each method are described in terms of their properties, structure, and function. The application of polymers shows great promise in achieving a highly efficient separation, especially in the areas of membrane separation and water purification. The rational design of new multifunctional polymers with triggered functions presumably presents new opportunities for the development of advanced separation methods.  相似文献   

15.
廖玮婷  解新安  李璐  李雁  樊荻  孙娇  王鑫 《化工进展》2019,38(5):2205-2211
通过研究木质素分别在超临界甲醇和乙醇溶剂中的液化过程,分析反应温度(260~340℃)及反应时间(0~120min)对木质素在两种溶剂中的转化率、生物油收率及其组分差异的影响。实验表明,木质素在超临界乙醇中的转化率及产物收率均高于甲醇。当反应温度340℃,反应时间60min,木质素在超临界乙醇中的转化率和生物油收率比在甲醇中分别提高了16.23%和11.54%,残渣收率降低了16.23%。通过GC-MS和FTIR对生物油和残渣分析,发现生物油组分中芳香族化合物相对含量较高,在甲醇和乙醇溶剂中分别达到66.13%和58.84%;随着反应时间的延长,甲醇溶剂中残渣的醚键官能团逐渐增强,而在乙醇溶剂中则先增强后减弱。分析认为在木质素降解过程中,超临界乙醇和甲醇均可产生氢自由基作为供氢体,攻击木质素及其大分子片段中的官能团,同时使液化产物中的活性片段减活,减弱重聚合反应,从而更利于芳烃产物的生成。而甲醇在液化过程中容易与木质素断键产生的苯酚中间体发生脱氢缩合反应,通过醚键聚合产生长链芳香族化合物,形成残渣,降低生物油收率。  相似文献   

16.
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   

17.
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.  相似文献   

18.
The dentate gyrus (DG), an important part of the hippocampus, plays a significant role in learning, memory, and emotional behavior. Factors potentially influencing normal development of neurons and glial cells in the DG during its maturation can exert long-lasting effects on brain functions. Early life stress may modify maturation of the DG and induce lifelong alterations in its structure and functioning, underlying brain pathologies in adults. In this paper, maturation of neurons and glial cells (microglia and astrocytes) and the effects of early life events on maturation processes in the DG have been comprehensively reviewed. Early postnatal interventions affecting the DG eventually result in an altered number of granule neurons in the DG, ectopic location of neurons and changes in adult neurogenesis. Adverse events in early life provoke proinflammatory changes in hippocampal glia at cellular and molecular levels immediately after stress exposure. Later, the cellular changes may disappear, though alterations in gene expression pattern persist. Additional stressful events later in life contribute to manifestation of glial changes and behavioral deficits. Alterations in the maturation of neuronal and glial cells induced by early life stress are interdependent and influence the development of neural nets, thus predisposing the brain to the development of cognitive and psychiatric disorders.  相似文献   

19.
Sepsis increases glucocorticoid and decreases IGF-1, leading to skeletal muscle wasting and cachexia. Muscle atrophy mainly takes place in locomotor muscles rather than in respiratory ones. Our study aimed to elucidate the mechanism responsible for this difference in muscle proteolysis, focusing on local inflammation and IGF-1 as well as on their glucocorticoid response and HDAC4-myogenin activation. Sepsis was induced in adult male rats by lipopolysaccharide (LPS) injection (10 mg/kg), and 24 h afterwards, rats were euthanized. LPS increased TNFα and IL-10 expression in both muscles studied, the diaphragm and gastrocnemius, whereas IL-6 and SOCS3 mRNA increased only in diaphragm. In comparison with gastrocnemius, diaphragm showed a lower increase in proteolytic marker expression (atrogin-1 and LC3b) and in LC3b protein lipidation after LPS administration. LPS increased the expression of glucocorticoid induced factors, KLF15 and REDD1, and decreased that of IGF-1 in gastrocnemius but not in the diaphragm. In addition, an increase in HDAC4 and myogenin expression was induced by LPS in gastrocnemius, but not in the diaphragm. In conclusion, the lower activation of both glucocorticoid signaling and HDAC4-myogenin pathways by sepsis can be one of the causes of lower sepsis-induced proteolysis in the diaphragm compared to gastrocnemius.  相似文献   

20.
Frick F  Hume R  Robinson IC  Edén S  Oscarsson J 《Lipids》2008,43(4):313-324
Transgenic Late-onset OBesity (LOB) rats slowly develop a male-specific, autosomal dominant, obesity phenotype with a specific increase in peri-renal white adipose tissue (WAT) depot and preserved insulin sensitivity (Bains et al. in Endocrinology 145:2666–2679, 2004). To better understand the remarkable phenotype of these rats, the lipid metabolism was investigated in male LOB and non-transgenic (NT) littermates. Total plasma cholesterol (C) levels were normal but total plasma triacylglycerol (TAG) (2.8-fold) and hepatic TAG content (25%) was elevated in LOB males. Plasma VLDL-C and VLDL-TAG levels were higher while plasma apoB levels were 60% lower in LOB males. Increased hepatic TAG secretion explained the increased VLDL levels in LOB males. The hepatic gene expression of FAS, SCD-1, mitochondrial (mt)GPAT, and DGAT2 was up-regulated in both old obese and young non-obese LOB rats. Lipoprotein lipase (LPL) activity in heart and epididymal white adipose tissue (WAT) was unchanged, while LPL activity was increased in peri-renal WAT (30%) and decreased in soleus muscle (40%). Moreover, FAS, SCD-1 and DGAT2 gene expression was increased in peri-renal, but not in epididymal WAT. Basal lipolysis was reduced or unchanged and β-adrenergic stimulated lipolysis was reduced in WAT from both old obese and young non-obese LOB rats. To summarize, the obese phenotype of LOB male rats is associated with increased hepatic TAG production and secretion, a shift in LPL activity from skeletal muscle to WAT, reduced lipolytic response in WAT depots and a specific increase in expression of genes responsible for fatty acid and TAG synthesis in the peri-renal depot. F. Frick and R. Hume contributed equally to this work.  相似文献   

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