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1.
水厂污泥的铝含量高,是一种重要的铝再生资源。研究了液相离子交换萃取法铝回收技术。采用P204-煤油作为萃取剂,与水厂污泥的酸溶浸出液反应,经3级错流萃取,铝萃取率可达96.3%。以5 mol/L硫酸为反萃剂,在相比(VO∶VA)为5∶1的条件下经3级反萃,铝反萃率达到98.9%,反萃液符合液态商品硫酸铝的质量标准,可作为饮用水处理的混凝剂回用。  相似文献   

2.
实验发现的协萃混合物[二(2-乙基己基)膦酸和2-乙基已基膦酸的煤油混合物]对于从氯化锌溶液中萃取铁(Ⅲ)具有相当高的选择性。本文主要研究了稀释剂、水相酸度、接触时间、温度及反萃剂浓度等参数对铁(Ⅲ)萃取和反萃取的影响。其最佳工艺条件为:水相酸度pH=0.5:萃取和反萃取温度为30~40℃;反萃剂盐酸浓度为6mol/L;萃取和反萃取级数分别为2~3级和3~4级。此外,测定了有机混合物的最大载荷(35.22g/L)及萃取剂的循环使用的效率同题。最后对协萃的机理进行了初步探讨,得出了协萃图,算出了协萃系数(R=3.82)。  相似文献   

3.
实验获知,N,N-二(1-甲基庚基)-乙酰胺(N503)的萃取效果优于醇、酮类萃取剂;有机相中加入长碳链酸性含磷萃取剂(OA-4),显示了一定的协萃效应。以5份N503-10份OA-4-20份TBP-65份磺化煤油(体积比)为萃取体系,在[HCl]=5mol/L,相比1∶1,[WO_3]_(2)=50.11g/L,W/P=11.9时,进行文题研究,结果表明:D_W≈1.16×10~3,用2mol/L氨水反萃,单级反萃率≈60%。初步探讨了协萃机理,在[HCl]=4~6mol/L时,N503-OA-4萃取磷钨酸为离子缔合萃取。N503质子化后,与磷钨杂多酸根阴离子缔合,OA-4则作为配位体进入协萃络合物以降低络合物的亲水性,进一步提高分配比。其协萃络合物的组成认为是(?)_2~+·[HPW_(12)O_(40)]~(2-)·(HA)  相似文献   

4.
发现了P538与P204的混合溶剂对文题有很强的协同效应。研究了该体系的萃取行为和性质,考察了混合溶剂的配比、磷酸浓度、两相接触时间、温度等因素对萃取行为的影响,从而确定了分离的最佳工艺条件:温度298K;平衡时间420s;溶剂配比为等摩尔的P538与P204及含40(v)%煤油;相比为1/2,2级逆流萃取;反萃取为:反萃余相浓度(?)=4.4kg/m~3,相比为1,温度298K,盐酸浓度为6kmol/m~3,理论级数为3级。初步研究了该协萃体系的萃取机理,萃合比为2。  相似文献   

5.
研究了以TBP从盐酸溶液中萃取分离锡与锌,发现如用煤油作稀释剂,则萃取过程会出现第三相。选用MIBK或癸醇作调相剂来消除第三相。作者解释了当用MIBK作调相剂,盐酸浓度大于7mol/L时,又会出现第三相的原因。萃取的最佳条件为:25%TBP-10%MIBK(或癸醇)-65%煤油;室温;6mol/L HCl;负载有机相中的杂质离子Zn~(2+)用6mol/L HCl洗涤,一次洗涤率达95%左右;负载有机相中的锡用0.24mol/L HCl反萃。实验比较了TBP萃取Sn~(4+)与Sn~(2+)的性能,解释了Sn~(4+)比Sn~(2+)略易萃取的原因。由于Sn~(4+),Zn~(2+)的竞争萃取,D_(Zn~(2+))随初始水相中[Sn~(4+)]的增加而减小,但当[Sn~(2+)]小于18g/L时,D_(Zn~(2+))几乎不变。  相似文献   

6.
研究了以TBP从盐酸溶液中萃取分离锡与锌,发现如用煤油作稀释剂,则萃取过程会出现第三相。选用MIBK或癸醇作调相剂来消除第三相。作者解释了当用MIBK作调相剂,盐酸浓度大于7mol/L时,又会出现第三相的原因。萃取的最佳条件为:25%TBP-10%MIBK(或癸醇)-65%煤油;室温;6mol/L HCl;负载有机相中的杂质离子Zn~(2+)用6mol/L HCl洗涤,一次洗涤率达95%左右;负载有机相中的锡用0.24mol/L HCl反萃。实验比较了TBP萃取Sn~(4+)与Sn~(2+)的性能,解释了Sn~(4+)比Sn~(2+)略易萃取的原因。由于Sn~(4+),Zn~(2+)的竞争萃取,D_(Zn~(2+))随初始水相中[Sn~(4+)]的增加而减小,但当[Sn~(2+)]小于18g/L时,D_(Zn~(2+))几乎不变。  相似文献   

7.
以三烷基氧膦(TRPO)为萃取剂,磺化煤油为稀释剂,考察了文题的影响因素。确定了萃取过程的最佳工艺条件:萃取剂组成50%TRP0-50%磺化煤油;室温;初始水相的pH值1-3。负载有机相中的羟基乙酸可有去离了水反萃,90℃下一次反萃率可达73.4%。依实验确定的萃取及反萃平衡等温线,可得到萃取及反萃的理论级数分别为5和7级。TRPO萃取羟基乙酸为一放热反应,萃取反应的热效应为-14.8kj/mol  相似文献   

8.
石油亚砜是一种低毒、价廉的萃取剂。本文对石油亚砜对钼(Ⅵ)的萃取条件和反萃取条件以及萃取的机理进行了研究。结果表明,在室温下,石油亚砜对pH=1.0-2.0、钼(Ⅵ)浓度为0.01-0.1 M的一级萃取率E(%)达到90%以上;一级反萃率也在90%以上;乳化问题亦获得完满解决。经对萃取机理的初步研究,可以认为石油亚砜萃取铝(Ⅵ)是属于离子缔合型萃取体系,被萃物为:  相似文献   

9.
文题的最佳工艺条件为:25%TBP-10%癸醇-65%煤油,3mol/LHCl,20~30℃。负载有机相中的杂质离子Zn~(2+),Cu~(2+),In~(3+),Pb~(2+)用约5mol/L盐酸洗涤除去。负载有机相中的Sn~(4+)用0.24mol/L HCl反萃。萃取及反萃取的理论级数分别为2和7级。  相似文献   

10.
我国某油田的柴油硫醚主体是五元及六元单环硫醚的混合物。该石油硫醚氧化所得产物,经分析研究证实为亚砜,能萃取柠檬酸,以氢键和柠檬酸形成萃合物。萃取平衡是个放热反应。△H为-5.213kJ/mol。80%石油亚砜甲苯溶液对柠檬酸水溶液(浓度为67g/L,含NaCl 60g/L)进行四级错流萃取(相比1:1,20℃),萃取率为99%,高于相同条件下磷酸三丁酯的萃取率。以6%NaCl水溶液对柠檬酸浓度为35.4g/L的80%石油亚砜甲苯液进行四级错流反萃(相比1:1,20℃),反萃率为94%。石油亚砜萃取含Ca~(2+)、Mg~2和Fe~(3+)的柠檬酸时能选择性萃取柠檬酸,但Fe~(3+)能同时被萃取。  相似文献   

11.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

12.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

13.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

14.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

15.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

16.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Journal of Nanjing Medical University (English Edition) JNMU, sponsored by Nanjing Medical University, was established in 1987. It is a bimonthly comprehensive English medical journal published locally and abroad.Since 2007, Journal of Nanjing Medical University (English Edition )was granted Elsevier the full publishing and distribution rights worldwide for the Electronic Edition, excluding the People's Republic of China.  相似文献   

19.
Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P< 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P< 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.  相似文献   

20.
ANTI-PROLIFERATION EFFECT OF ORIDONIN ON HL-60 CELLS AND ITS MECHANISM   总被引:4,自引:0,他引:4  
Objcetive To investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells in vitro in culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was detected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred. Results Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especially after cells were treated 48-60 hours by oridonin. Conclusions Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells in vitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.  相似文献   

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