采用集中粗选分步精选流程浮选萤石

本文叙述了该厂为提高萤石浮选精矿品位与回收率，排除重晶石对萤石浮选的干扰，将萤石按不同品级加以回收，获得了萤石精矿品位为９６％－９７％、萤石次精矿品位为８５％－８８％，其实际总回收率为７５％－８０％的较好生产指标。     

柿竹园钨钼铋尾矿回收萤石可选性试验研究

介绍了柿竹园钨钼铋尾矿的工艺矿物学性质及可选性试验研究。根据尾矿性质,确定采用预先筛分粗颗粒直接抛尾,细粒级进入萤石浮选,粗精矿精选,产品强磁脱硅,部分中矿单独再选产出低品位萤石精矿的混合流程。最终获得高品位萤石精矿,CaF297．22％,回收率为55．06％,低品位萤石精矿CaF290．89％,回收率为8．16％。     

江西永丰萤石矿选矿研究

江西永丰萤石矿选厂采用一段磨选流程，其精矿含硅总在１％以上，严重超标．通过系统的试验，采用阶段（２段）磨选工艺，使硅能降至０．６％以下，并且萤石精矿品位和收率也有所提高，达到了提交精矿质量的目的     

利用浮选柱提高微细粒萤石回收率的工业试验

为了解决龙泉市砩矿有限责任公司萤石浮选尾矿中微细粒萤石流失严重的问题,引入充气式浮选柱处理浮选机浮选尾矿,通过浮选柱参数优化确定了最终的工业生产流程.经连续运转72 h共计9个班次不间断工业生产得到了萤石精矿含CaF297.42％、CaF2回收率为96.59％的工业试验指标,该指标相比原生产指标,精矿中CaF2实际回收...     

含钨萤石中矿高压浸出钨、铷试验研究

含钨萤石中矿采用常压碱浸、苏打焙烧等工艺时,钨、铷及萤石回收率均不高.对该矿样进行了高压烧碱浸出工艺及盐酸预处理+高压碱浸工艺方案的探索试验,并进行了关键影响因素——碱加入量条件试验.经验证,当矿样用100％盐酸预处理,将预处理渣用水洗至pH值约为7后,加入1.5倍理论量烧碱+0.5倍理论量纯碱进行高压浸出试验,钨浸出率可达99％,铷可达84％,萤石分解率为50％.采用高压循环浸出后,碱耗可降低50％左右.该工艺指标好,三废可达标排放,经济效益明显.     

高梯度磁选分选白云鄂博萤石矿物研究

白云鄂博萤石浮选精矿经超导磁分离技术处理后,超导精矿中萤石品位从85.21％提高至96.84％,稀土品位从5.29％降低至0.11％.利用超导高梯度磁选方法,可以有效提高白云鄂博矿萤石浮选精矿中萤石品位和降低稀土矿物含量,可缩短萤石精矿的浮选流程,减少药剂用量,降低其他功耗,有效的节约了成本.     

福建某萤石矿选矿试验研究

福建某萤石矿含CaF2为18%左右,属于低品位萤石矿,试验采用预先脱硫-浮选萤石工艺,常规流程闭路试验可获得一个萤石精矿品位为90.36%,回收率为77.33%的萤石精矿;采用中矿再选流程可获得两个萤石精矿,萤石精矿1品位为97.37%,回收率为44.76%;萤石精矿2品位为86.65%,回收率为25.68%;综合萤石精矿品位为93.17%,回收率为70.44%的良好选矿指标。     

某钨尾矿综合回收低品位萤石浮选试验研究

某钨尾矿有用矿物萤石嵌布粒度细,萤石含量低,单体解离难,石英、方解石等脉石矿物含量高,试验研究了该钨尾矿萤石和脉石矿物的浮选分离行为,通过条件试验,选择HY为萤石捕收剂,酸化水玻璃+HF为脉石矿物抑制剂,研究最终确定了一段一次粗选.七次精选工艺流程.结果表明:在钨尾矿含萤石8.12%的条件下,闭路试验获得了精矿CaF₂品位95.36%,回收率61.39%的选矿指标,实现了资源的综合回收.      

萤石白钨石榴石浮选分离的新型药剂—LP系列捕收剂

本文用LP系列捕收剂浮选萤石、白钨、石榴石等单矿物和人工混合矿。试验结果表明,LP系列药剂对萤石有较强的捕收能力。在一定pH条件下可浮白钨,对石榴石捕收能力较弱。用LP—8为捕收剂分离萤石—白钨、萤石—石榴石混合矿得到好结果。用红外光谱和ζ电位测定研究了LP—8浮选萤石、白钨、石榴石的作用机理。     

提高萤石精矿质量的新途径

本文介绍提高刘家坪硫化氧化铅锌矿中萤石精矿质量的试验，其结果表明，采用石腊粗皂液分四次添加，分批刮泡，能增大萤石与重晶石的浮游差，取得了较好的分选效果。     

某堆场试验区软基处理工程效果分析

试验区采用真空联合堆载法进行软基处理,室内土工试验表明,地基的力学性质有一定的提高,处理后淤泥层含水率、孔隙比及压缩系数分别下降了9.32%、6.59%和2.68%;而湿密度、φ、c及压缩模量分别提高了1.09%、40.48%、10.02%和13.53%;现场十字板抗剪强度试验结果表明,埋深15m以上淤泥不排水十字板抗剪强度平均增长了25.9%。通过现场沉降监测和孔隙水压力监测的试验数据,试验区经110d的真空联合堆载法处理,理论估算地基平均固结度≤90%。处理措施需要进一步优化。     

Correlation between antigen-specific IL-2 response test and provocation test for egg allergy in atopic dermatitis

BACKGROUND: The antigen-specific interleukin-2 response (AIR) test using lymphocytes is effective in searching for the antigen which causes allergic diseases and understanding their disease activity. OBJECTIVE AND METHODS: The correlation between the raw egg oral provocation test and egg white antigen-specific interleukin-2 (IL-2) response test was investigated in 123 children with infantile atopic dermatitis and 13 children with bronchial asthma. RESULTS: Among the 83 who showed positive reactions to provocation, 75 also reacted positively to the AIR test (sensitivity, 90.4%), while among the 53 children who showed negative responses to antigen provocation, 45 produced negative responses to the AIR test (specificity, 84.9%). The specificity of egg white IgE RAST score and skin-prick test are 88.7 and 81.3% which are comparable to that of the AIR test. However, their sensitivity was low (38.6 and 66.7%). In the patterns of symptom developed in the provocation AIR displayed late and delayed type allergic responses in addition to the immediate type which RAST reflected. The RAST-negative group composed of 98 patients included 51 (52.0%) who exhibited positive reactions to the provocation test. Among these 44 responded positively to the AIR test (86.3%). CONCLUSION: The AIR test is effective for screening egg white antigen as part of the tests for antigens responsible for allergic diseases and as a test to ascertain the relevant antigens, and that the conditions that could not be diagnosed by RAST can be detected by the AIR test.     

Haemagglutination system for the simultaneous detection of LPS and anti LPS antibodies of S.typhi

In view of the limitations of Widal test for the diagnosis of typhoid, haemagglutination test using sensitized sheep red blood cells was designed at our laboratory. The test gave only 1.8% positivity at 1:40 dilution among 500 normal persons. Eighteen of the 30 culture proven cases gave the HA test positive while the positivity was 62.5% among suspected cases of typhoid. Thus, the anti LPS haemagglutination test showed a sensitivity of 60% and specificity of 98.2%. The positive predictive value and negative predictive value were 66.66% and 96.7% respectively. The haemagglutination inhibition test was also developed for the detection of LPS antigen of S. typhi in the serum samples of typhoid cases and could detect 1.5625 micrograms/ mL of S. typhi LPS antigen but failed to detect LPS in the sera of bacteriologically proven cases of typhoid. However, it could detect the growth of simulated blood cultures of S. typhi within one hour of inoculation and did not give any cross reactions with other bacterial cultures. The data suggest that the haemagglutination test could be a good adjunct for Widal test and the haemagglutination inhibition test could help the early detection of S. typhi in culture.     

Diffusion-weighted MR imaging with a single-shot echoplanar sequence: detection and characterization of focal hepatic lesions

BACKGROUND: The aim of this study was to establish the feasibility, safety, and diagnostic accuracy of the dipyridamole echocardiography test in patients with severe aortic valve stenosis for noninvasive detection of coexisting coronary artery disease. METHODS: The high-dose dipyridamole echocardiography test was performed in 52 patients with severe aortic stenosis; all patients also underwent coronary angiography, independent of test results, before cardiac operation. RESULTS: The dipyridamole echocardiography test was completed without major complications. One patient had transient atrial fibrillation that was reversed by aminophylline. Thirty-one patients (60%) had a negative test result; all had normal coronary arteries. Ten of the 21 patients (48%) with a positive test result had coexisting coronary artery disease. The positive predictive value of the dipyridamole echocardiography test for detection of coronary disease in patients with severe aortic stenosis was 48%. The negative predictive value was 100%. The sensitivity was 100% and the specificity was 74%. CONCLUSIONS: Dipyridamole echocardiography is a safe and feasible tool in patients with severe aortic stenosis eligible for a cardiac operation. A negative test result reliably rules out a significant stenosis, whereas a positive one is much less accurate in predicting coronary artery disease.     

Studies on crude drugs originated from gentianaceous plants. II. Determination of swertiamarin, the major bitter principle of Swertiae herba and related crude drugs (author''s transl)

The LOT test was administered to 100 normal-hearing subjects ranging in age from seven years, six months to 10 years, six months. The test was conducted at 500, 1000, 2000, and 4000 Hz with 99 subjects who were able to perform the required task. The LOT test misclassified (false-positive result) only 4% of the normal-hearing children at 1000 Hz. The test misclassified 3% at 2000 Hz, 3% at 4000 Hz, and 14% at 500 Hz. A new criterion for the use of the LOT test with children is proposed which reduced the percentage of misclassification to 2% at 1000, 2000, and 4000 Hz. The frequency of 500 Hz is not recommended for the preadolescent population.     

Usefulness of angiotensin converting enzyme inhibitors in the diagnosis of renovascular hypertension. III. Evaluation of the validity of the captopril test and the reno-scintigraphic captopril test in the diagnosis of renovascular hypertension according to accepted criteria

The aim of the study was to evaluate diagnostic validity of captopril test and scintigraphic test before and after captopril for the detection of renovascular hypertension (RVH) according to applied criteria. Employing blood pressure response to captopril as a criteria sensitivity was 37.0%, specificity 92.1%, positive predictive value 75.0% and negative predictive value 70.2% in the captopril test. Applying plasma renin activity (PRA) response to captopril as a criteria sensitivity was 92.5%, specificity 100%, positive predictive value 100% and negative predictive value 96.0% in the same test. Renin captopril test has excellent sensitivity and positive predictive value, is easy to perform and inexpensive and therefore may be a useful screening test for RVH in unselected population. With the own criteria used, captopril renoscintigraphy detected RVH with 87.5% sensitivity, 91.7% specificity, 87.5% positive predictive value and 91.7% negative predictive value. Captopril renoscintigraphy is an accurate diagnostic test for the identification of RVH in a clinically selected high-risk population. Common evaluation of both tests does not improve their accuracy in diagnosis of RVH.     

Drosophila melanogaster, Vicia faba and Arabidopsis thaliana short-term bioassays in genotoxicity evaluation of air and soil samples from sites surrounding two industrial factories in the Czech Republic

The Somatic Mutation and Recombination Test (SMART) in wing cells of Drosophila melanogaster, the Vicia faba cytogenetic tests-Sister Chromatid Exchange (SCE) and Micronucleus Test (MN), and the Müller test for gametic mutations in Arabidopsis thaliana were used for genotoxicity testing of environmental samples of pollutants from the surroundings of LACHEMA chemical factory (Brno, Czech Republic) and DEZA factory in Valasské Mezirící (Moravia, Czech Republic). Tested soil and air samples were taken from the near vicinity of both factories. The surroundings of both sites are heavy loaded by exhalation of chemicals from the factories. Chemical analyses of the 16 Polycyclic Aromatic Hydrocarbons (PAHs) according to the United States Environmental Protection Agency (US EPA) list of priority pollutants and heavy metals were performed in both soil and air samples. The Drosophila wing spot test was positive in 70.6% of the tested samples, the Vicia sister chromatid exchange test in 62.5%, and the Arabidopsis Müller test in 58.9%. The micronucleus Vicia faba test was quite insensitive in tested environmental samples. The concordance between SMART and SCE was 62.5%, between SMART and Müller test 76.5%, and between Müller test and SCE 100%. Total concordance of these three tests was 79.7%. Müller test for gametic mutation in Arabidopsis thaliana and cytogenetic SCE test in Vicia faba seem to be quite sensitive and convenient plant bioassays for assessing the mutagenic potential of environmental agents, when compared to the SMART test in Drosophila melanogaster.     

Erythropoietin treatment: concept and controversy

We assessed two new rapid urease tests, the Helicobacter Urease Test (HUT, Astra, Sweden) and the Polish test, for accuracy, reaction time, and the effect of biopsy site and bacterial density on test characteristics and time to positivity. A prospective study was conducted in two groups of patients: 64 consecutive patients undergoing upper endoscopy for dyspepsia and 61 consecutive patients with duodenal ulcer on upper endoscopy. In the first group, test accuracy, time to positivity, and possible associations with biopsy site and bacterial density were assessed between the tests. In the second group, the two new tests were compared with the CLOtest for time to positivity and effect of bacterial density on test outcome. The Polish and HUT test had similar specificities (97%), but the Polish test was more sensitive (90.3% vs. 80.7%). The Polish test was positive within 10 minutes in 55% of the positive patients compared with 10% for the HUT test. There was no association between bacterial density (by histologic count) and reaction time in either test or in the CLOtest in the second group. The Polish test was more accurate and had a quicker time interval to positivity than the HUT. There was no significant association between bacterial density and reaction time in any of the urease tests assessed, and the biopsy site did not affect test accuracy in the HUT test.     

甘肃某白钨矿选矿工艺试验研究

对甘肃某白钨矿的矿石性质进行了分析研究,根据物质成分的研究结果和各种矿物的特点,首先进行了预选试验,确定了小型选矿流程试验,进一步进行了扩大连续选矿流程试验研究,最终试验结果为:白钨精矿产率为0.94%,品位WO365.07%,回收率78.18%,细泥白钨精矿产率为0.10%,品位WO332.29%,回收率4.19%。试验结果可以作为建厂设计的技术依据。     

Xanthogranulomatous pyelonephritis: conservative therapy in the para-nephritic stage. Apropos of a case]

OBJECTIVE: To determine the diagnostic and prognostic test qualities of the enzyme linked immunosorbent assays (ELISA) for rheumatoid factor isotypes in rheumatoid arthritis (RA), and to compare them with the latex fixation test. METHODS: Rheumatoid factor tests were performed in 1988 consecutive new rheumatology outpatients within two months after their first visit to the outpatient clinic of the Department of Rheumatology of Leiden University hospital. The sensitivity, specificity, accuracy, and predictive values of the tests in discriminating RA from non-rheumatoid arthritis and erosive from non-erosive disease after two years of follow up were determined and presented as receiver operating characteristic curves and post-test probability curves. RESULTS: The sensitivity of the ELISA for IgG, IgA, and IgM rheumatoid factor for RA versus all controls at optimal cut off titres was 72%, 44%, and 69%, respectively; the specificity was 52%, 84%, and 86%. For the latex fixation test the sensitivity was 66% and the specificity 91%. The post-test probability of RA, at a clinical prevalence rate of 12%, given a positive test result in the ELISAs for IgG, IgA, and IgM rheumatoid factor and the latex fixation test, was 17%, 27%, 40%, and 49%, respectively; with negative test results the probability was 7%, 8%, 5%, and 5%, respectively. The specificity of all tests in discriminating erosive from non-erosive RA at two years was low: 41%, 44%, 47%, and 58% for the ELISAs for IgG, IgA, and IgM rheumatoid factor and the latex fixation test, respectively. CONCLUSION: The ELISAs for IgG and IgA rheumatoid factor are of no significance in diagnosing RA and in the prediction of erosive disease. The ELISA for IgM rheumatoid factor is a reasonable alternative for the latex fixation test when age and gender are taken in to consideration. The specificity of all rheumatoid factor tests in discriminating erosive from non-erosive RA is low.