含氰废水处理方法的研究

针对采用湿法提纯金泥的企业处理含氰化物的废水,采用氯化法提纯金泥中的黄金,由于金泥含有大量氰化物,在预浸工序产生的废水中氰化物含量达到2 000 mg/L 左右。国家规定排放废水中含有的氰化物浓度不得超过0.5 mg/L,本企业要求排放废水中氰化物的浓度不得超过0.04 mg/L,预浸产生的废水必须经过脱氰化处理才能排放。经过实际研究,结合精炼厂现有工艺设备,采用酸性氯化法和活性炭吸附法相结合来脱出废水中的氰化物,经过处理的废水总氰含量低于0.04 mg/L,达到排放标准,最后排入焦家金矿选厂。     

某金矿氰化贫液净化试验工艺参数研究

某金矿氰化提金过程产生的氰化贫液中总氰化合物质量浓度3 303.5 mg/L,硫氰酸盐质量浓度3 855.0 mg/L,铜质量浓度1 527.2 mg/L,试验确定了采用酸化吹脱-碱液吸收法去除影响选矿指标的铜离子并回收氰化物的可行性,优化了酸化吹脱法的工艺条件。在最佳试验条件下,氰化贫液中总氰化合物去除率达99.06%,铜去除率98.65%,氰化物回收率78.00%,处理后的溶液进行氰化浸出试验,效果较好,即返回液对氰化浸出过程无影响。     

The use of a complex cobalt compound as a cyanide antidote

The medical effect of the cobalt (III) complex compound [Co(DH)2(H2O)2]Cl poisoning by potassium cyanide has been experimentally found. The poisoning has been caused by intravenous potassium cyanide, 1 mg/kg. The aqueous solution of the complex was added the same to cyanide in doses of 40 and 80 mg/kg. The poison and antidote effects were controlled by bioelectrical tests of the brain and heart. The advantage of the preparation is its direct interaction with cyanide and significantly lower doses as compared with the well-known anticyanide antidotes.     

Sodium nitroprusside: pharmacology, toxicology and therapeutics

Sodium nitroprusside is a potent, effective, and readily reversible direct vasodilating agent. It is broken down by hemoglobin into cyanide, which is in part detoxified by liver and kidney to thiocyanate. Some cyanide, especially in nitroprusside- "resistant" individuals who need large amounts of the drug, appears to remain free to cause cyanide poisoning. Patients requiring inordinate amounts probably should not continue to receive the drug, although maximum dosage limits for long-term therapy are not established. Blood thiocyanate levels do not indicate the extent to which free cyanide is limiting oxygen utilization in essential tissue, nor do blood cyanide levels. Metabolic acidosis, elevated lactate levels, elevated lactate/pyruvate ratios, and elevated mixed venous blood oxygen content are at present the best indications of the presence of cyanide poisoning during nitroprusside administration. Nitroprusside appears useful for induction of hypotension during surgery, and for treatment of hypertensive emergencies from all causes, although continuance for more than a few days is probably unwise. The reductions of cardiac afterload and ventricular filling pressure by nitroprusside appear useful in treatment of severe myocardial failure or infarction, but studies of myocardial cyanide toxicity are needed before complete acceptance of this therapy is warranted. Initial dose rates between 0.5 and 1.5 mug/kg/min are recommended only as starting points for very careful titration. Total projected intra-operative dosage should be calculated as quickly as possible and should not exceed 3-3.5 mg/kg. It is hoped that future studies will reveal the maximum dose of nitroprusside that can safely be metabolized in a 24-hour period, and may indicate that cofactors of rhodanase such as thiosulfate, or cobalamins such as hydroxocobalamin, can be administered with nitroprusside to prevent cyanide poisoning.     

Improved colorimetric determination of serum zinc

We show how zinc may easily be quantified in serum by first using an optimum concentration of guanidine hydrochloride to cause release of zinc from proteins, followed by complexation of released metals with cyanide. The cyanide complex of zinc is preferentially demasked with chloral hydrate, followed by a colorimetric reaction between zinc and 4-(2-pyridylazo)resorcinol. This is a sensitive water-soluble ligand; its complex with zinc has an absorption maximum at 497 nm. Values found by this technique compare favorably with those obtained by atomic absorption spectroscopy.     

Serum iron concentrations and symptoms of acute iron poisoning in children

STUDY OBJECTIVE: To determine whether serum iron concentrations correlate with the development of symptoms of iron poisoning in children. DESIGN: A retrospective study of medical records from January 1976 through June 1992. SETTING: A tertiary care children's medical center. PATIENTS: Criteria for patient selection included an acute ingestion of iron-containing drugs, measurement of serum iron prior to deferoxamine administration, and a serum iron concentration (obtained within 2-9 hours of exposure) that was greater than 150 micrograms/dl (27 mumol/L). Of the 128 children who were hospitalized for acute iron poisoning, 92 patients (mean age 2.3 +/- 2.2 years) met the selection criteria. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The mean (+/-SD) serum iron concentrations (microgram/dl) of patients who exhibited cardiovascular instability (725 +/- 555, n = 6; p < 0.001) differed from those categorized with central nervous system changes (373 +/- 77, n = 30), gastrointestinal symptoms (334 +/- 83, n = 44), and no symptoms (368 +/- 102, n = 12). Serum iron concentrations in patients with cardiovascular instability ranged from 205-500 micrograms/dl (37-269 mumol/L), whereas those with no symptoms ranged from 170-513 micrograms/dl (30 to 92 mumol/L) demonstrating considerable overlap of ranges. CONCLUSIONS: Serum iron concentrations do not necessarily relate to acute toxicity, and further study is needed to demonstrate the value of serum iron concentrations and to identify alternative strategies in the emergency assessment of the acutely poisoned child.     

Influenza virus inhibits cleavage of the HSP70 pre-mRNAs at the polyadenylation site

BACKGROUND: Tocotrienols, lipid-soluble antioxidants with vitamin E activity, have been reported to lower LDL-cholesterol concentrations and platelet aggregation in men, but results are contradictory. OBJECTIVE: To examine in detail the effects of a vitamin E concentrate rich in tocotrienols on serum lipoproteins and on platelet function in men at risk for cardiovascular disease. DESIGN: In this randomized, double-blind, placebo-controlled parallel trial, 20 men received daily for 6 wk 4 capsules, each containing 35 mg tocotrienols and 20 mg alpha-tocopherol; 20 other men received 4 capsules daily, each providing 20 mg alpha-tocopherol. All men had concentrations of serum total cholesterol between 6.5 and 8.0 mmol/L or lipoprotein(a) concentrations > 150 mg/L. RESULTS: Compliance was confirmed by changes in serum tocopherol and tocotrienol concentrations. Serum LDL cholesterol in the tocotrienol group was 4.80 mmol/L before and 4.79 mmol/L after intervention, and increased from 4.70 to 4.86 mmol/L in the placebo group (95% CI for the difference: -0.54, 0.19 mmol/L; P = 0.333). Also, changes in HDL cholesterol, triacylglycerol, lipoprotein(a), and lipid peroxide concentrations did not differ between the groups. After adjustment for differences in initial values, no effects were found on collagen-induced platelet aggregation velocity, maximum aggregation, or thromboxane B2 formation in citrated whole blood. ATP release, however, was lower in the tocotrienol group. Urinary thromboxane B2 and 11-keto-thromboxane B2 concentrations and coagulation and fibrinolytic measures did not change. CONCLUSION: The tocotrienol supplements used had no marked favorable effects on the serum lipoprotein profile or on platelet function in men with slightly elevated lipid concentrations.     

Primary angiosarcoma of the breast

In order to study the effects of propylthiouracil (PTU) on the fetal thyroid and serum concentration, 9 women undergoing therapeutic abortion at the second trimester of pregnancy were given a single dose of 50, 100 and 150 mg PTU respectively. The concentrations of PTU in the maternal and fetal serum and those in the fetal thyroid tissues were determined with a high-performance liquid chromatographic method, the lowest limit of which was 25 micrograms/L. After an oral bolus of PTU, the PTU concentrations in the maternal serum reached a peak level after one hour and there was a wide individual variation of the peak value. The study showed PTU could be transferred through the placenta from the maternal blood to the fetal blood and highly accumulated in the fetal thyroid tissues. The fetal serum PTU concentrations correlated with those of their mothers at the same time (r = 0.7084, P < 0.02) and the concentrations in the fetal thyroid tissues could be evaluated by the maternal serum peak level after an oral bolus. PTU didn't inhibit the fetal thyroid peroxidase activity even when the maternal serum PTU concentration reached 4 mg/L, which is the lowest effective therapeutic concentration of PTU in adults.     

堆浸富液中高铜载金炭吸附金的影响因素研究

利用正交试验法对高铜载金炭吸附金的影响因子进行了研究。通过对试验数据进行极差和方差分析表明:富液铜质量浓度、液炭比、p H值、氰化钠质量浓度、吸附时间等5种因素对高铜炭吸附金的影响权重依次减小;其优化工艺条件为富液铜质量浓度越低越好,液炭比5∶1,p H值9.0,氰化钠质量浓度400 mg/L,吸附时间0.5 h。在该试验条件下,富液铜质量浓度只有小于500 mg/L才可避免高铜炭对铜的吸附,进而保证活性炭吸附工艺的正常运行。     

Recovery of Silver and Gold from Cyanide Solution by Magnetic Species Formed in the Electrocoagulation Process

Cyanidation is the predominant process by which gold and silver are recovered from their ores in metallurgical operations, and it is recognized that the Carbon in Pulp, the Merrill–Crowe, the Ion Exchange, and Solvent Extraction processes are used for concentration and purification of gold and silver from cyanide solutions. Among other available options for recovery of precious metals from cyanide solutions, Electrocoagulation (EC) is a very promising water and wastewater electrochemical technique that does not require high concentrations of silver and gold in cyanide solutions to yield excellent results. In this work, an introduction to the fundamentals of the EC process is given, followed by the conditions and results of the EC test run for removal of precious metals from cyanide solutions, and finally the characterization of the solid products formed during the EC process with X-ray Diffraction, SEM, and Transmission Mossbauer Spectroscopy. Results suggest that magnetite particles and amorphous iron oxyhydroxides are present (Lepidocrocite and Gohetite). With the EC process, the achieved removal efficiency of silver and gold from cyanide solutions, within 5 min, exceeded 99%.     

The CAG repeat within the androgen receptor gene and benign prostatic hyperplasia

Thalidomide, a glutamic acid derivative, has recently been shown to inhibit in vitro angiogenesis, the process of formation of new blood vessels. This Phase II study examined the pharmacokinetics of thalidomide in patients with clinically progressive hormone-refractory prostate cancer. Patients (aged 55 to 80 years) were randomized to two different arms, low dose versus high dose. Patients in the low-dose group were given 200 mg of thalidomide and patients in the high-dose group received 200 mg of thalidomide, with subsequent dose escalations to 1200 mg. Serial serum or blood samples were obtained for pharmacokinetic assessment after administration of a single oral dose or multiple daily dosing of thalidomide and were assayed by reversed-phase HPLC. Pharmacokinetic parameters for both the single and multiple dosing were calculated with ADAPT II. A one-compartment model best fit the data. After single dosing, the oral clearance and apparent volume of distribution for the low-dose regimen (n = 13) were 7.41 +/- 2.05 L/h and 66.93 +/- 34.27 L, respectively, whereas for the high-dose regimen (n = 11), these values were 7.21 +/- 2.89 L/h and 165.81 +/- 84.18 L, respectively. The elimination half-lives for the low and high dose were 6.52 +/- 3.81 and 18.25 +/- 14.08 h, respectively. After the multiple dosing of thalidomide, the oral clearance and apparent volume of distribution for the low-dose group (n = 10) were 6.35 +/- 1.64 L/h and 64.63 +/- 23.20 L, respectively, whereas for the high-dose group (n = 11), these values were 7.73 +/- 2.27 L/h and 167.85 +/- 82.08 L, respectively. The elimination half-lives for the low and high dose were 7.08 +/- 1.87 and 16.19 +/- 9.57 h, respectively. For both the single and multiple dosing of thalidomide, the apparent volume of distribution and half-life were significantly higher for the high-dose group than those for the low-dose group. The higher apparent volume of distribution may be attributable to several factors, such as change in absorption, protein binding, etc. A dose-proportional increase in thalidomide steady-state concentrations was seen after multiple daily dosing of thalidomide.     

Concentration of teicoplanin in the serum of adults with end stage chronic renal failure undergoing treatment for infection

We examined the adequacy of the following schedule for the administration of i.v. teicoplanin to patients with chronic renal failure: three doses of 6 mg/kg at 12 h intervals, a fourth dose 24 h later and then subsequent doses every 72 h. Eight infected patients undergoing dialysis were investigated, with serum antibiotic concentrations measured ten minutes before and one hour after administration. Mean trough concentrations were 6.9 +/- 3.1 mg/L on day two, 9.8 +/- 4.4 mg/L (day three), 9.2 +/- 4.8 mg/L (day six), 10.9 +/- 5.5 mg/L (day nine), 12.1 +/- 6.1 mg/L (day 12) and 14.8 +/- 8.0 mg/L (day 15). The proposed schedule achieved adequate trough serum teicoplanin concentrations by 48 h in six out of eight patients examined. The dosage regimen was well tolerated.     

过氧化氢氧化-亚铁盐沉淀联合工艺处理含氰尾矿试验研究

某金精矿冶炼企业含氰尾矿中总氰化合物及砷含量较高,采用过氧化氢氧化—亚铁盐沉淀联合工艺对其进行无害化处理,并对试验条件进行了优化。最佳试验参数:除氰阶段为过氧化氢用量2.0 mL/L,pH值6.0~6.5,反应时间2 h;除砷阶段为七水硫酸亚铁用量0.50 g/L,过氧化氢用量1.0 mL/L,pH值6.0~6.5,反应时间1 h。处理后的含氰尾矿压滤渣毒性浸出液中的总氰化合物和砷质量浓度均稳定低于HJ 943—2018《黄金行业氰渣污染控制技术规范》尾矿库处置标准要求,实现尾矿库堆存。     

Correlation between sizes and intracystic pressures of hydatid cysts

Serum cefuroxime concentrations were measured over a 12 h period in ten healthy adults following three iv dosing regimens: 750 mg cefuroxime, 1.5 g cefuroxime, and 750 mg cefuroxime with 1 g of probenecid given orally 3 h before the cefuroxime infusion. Probenecid prolonged the serum cefuroxime half-life by 63% (P < 0.05) with a significant increase in the mean time for which serum cefuroxime concentrations exceeded the MIC90 for common respiratory pathogens (2 mg/L) compared with either 750 mg cefuroxime (2.2 h, P < 0.05) or 1.5 g of cefuroxime (0.9 h, P < 0.05) without probenecid. The cost of the 750 mg cefuroxime dose plus probenecid is approximately half that of a 1.5 g cefuroxime dose.     

Physiologic differences between twin and single born beef calves in the first two days of life

Behavioral observations and hematological, serum biochemical and blood gas measurements were made on 8 naturally occurring twin calves during the first 48 hours of life. These values were compared to similar measurements collected from 30 single born calves, born under the same calving conditions. All calves survived to at least 3 weeks of age without physically detectable disease. Although the gestational age of the twins and singles were not different, the twins had a lower mean birth weight. Calving difficulty score, time interval to standing and time interval to nursing were not different between the 2 groups. Twin calves had significantly lower rectal temperatures, arterial oxygen tensions and blood glucose concentrations than the single calves through the first 12 hours of life. Hct, Hgb concentration, and RBC were lower in twin calves throughout the 48 hour period. The N:L ratio was lower in the twins at birth. Mean serum IgG1 concentrations were lower in twins only at 24 hours whereas IgM concentrations were lower at both 24 and 48 hours in twins. Serum chemistry value differences between twin and single calves were most numerous at 24 hours of age when serum proteins, urea nitrogen, total bilirubin, sodium, chloride, and total calcium concentrations were higher in the twins and serum phosphorus concentration was lower in the twins.     

Pathway engineering for the production of aromatic compounds in Escherichia coli

The standard enzymatic assay for quantification of D-sorbitol in plasma was adapted to the automatic analyzer Cobas Mira S. In the assay, NAD (reagent) in the presence of sorbitoldehydrogenase (SDH; start reagent) converts D-sorbitol to fructose with formation of NADH, which was detected automatically as the difference between the first and last readings at 340 nm. The sample blank values for each specimen were subtracted to exclude both endogenous D-sorbitol and sugars, which also react as substrates for SDH. The method is simple, rapid (40 samples/h), precise down to endogenous concentrations (coefficient of variation < 5%; limit of determination: 0.38 mg/L) and linear up to 100 mg/L. Samples with higher D-sorbitol concentrations were estimated after dilution. The method was used to measure disposition curves of sorbitol in volunteers after a single intravenous dose of 0.8 g sorbitol.     

Quantification of plasma hemoglobin in the presence of bilirubin with bilirubin oxidase

Owing to the overlapping absorption bands of hemoglobin and bilirubin, spectrophotometric determination of plasma free hemoglobin has been plagued by the interference of bilirubin when the latter is present in significant concentrations. To resolve this problem, bilirubin oxidase from Myrothecium verrucaria has been used to remove bilirubin in icteric samples. The enzyme converts bilirubin to biliverdin and eliminates its absorption in the 400 nm region. The absorbance of hemoglobin at 415 nm after Allen baseline correction is used to quantify its concentration. Intra-assay precision of this method on a sample containing 200 mg/L of free hemoglobin and 200 mg/L of bilirubin is 3.1 percent (n = 10), while the between-run precision is 3.8 percent (n = 10). Accuracy studies with samples containing 200 mg/L of bilirubin yielded a straight line: y = 0.90x + 2.31, Sy.x = 3.3, r = 0.99. These results demonstrate that this method can be used to determine free hemoglobin in icteric specimens.     

Using Complex Permittivity and Artificial Neural Networks for Contaminant Prediction

The use of the measured complex permittivity of electrolyte solutions for predicting ionic species and concentration is investigated. Four artificial neural networks (ANNs) are created using a database containing permittivities (at 1.0, 1.5, and 2.0 GHz) and loss factors (at 0.3, 1.5, and 3.0 GHz) of 12 aqueous salts at various concentrations. The first ANN correctly identifies cationic species in 83% of the samples and distinguishes between pure water and electrolyte solutions with 100% accuracy. The second ANN predicts cationic concentrations with a RMS error of 190 mg/L for the range of concentrations examined (0–3,910 mg/L) and explains 90% of the variability in these data. The third ANN correctly identifies 98% of the anionic species in samples and accurately distinguishes between pure water and anion-containing solutions. The last ANN predicts anionic concentrations with a RMS error of 164 mg/L for the range of concentrations examined (0–5,654 mg/L) with an r2 of nearly 98%.     

Effects of AT-I on murine cytokins productions and NK cell activity in vivo

The objective of this prospective study was to assess the prognostic value of dynamic and static liver function tests and clinical symptoms in pediatric patients with chronic end-stage liver disease in a serial examination including three evaluations at 3-month intervals. Of the 24 patients entering the study, six were given transplants within the observation period of 10 months. Of the remaining 18 patients who were considered in the final evaluation, five died before transplantation was possible. The variables included in the analysis were monoethylglycinexylidide (MEGX) formation from lidocaine, bilirubin, albumin, and creatinine serum concentrations, catalytic serum concentration of cholinesterase (CHE), prothrombin time (PT), factors II and V, serum amino acids, body weight, and presence of ascites. In nonsurvivors (n = 5), MEGX serum concentrations 30 min after intravenous administration of lidocaine (1 mg/kg body weight) were < 10 micrograms/L at the first examination. Statistically significant differences between nonsurvivors and survivors were observed for initial MEGX test results (p = 0.0089) and serum bilirubin concentrations (p = 0.009), as well as for the last available MEGX and bilirubin data from each patient (p = 0.017 and 0.016, respectively). At a diagnostic sensitivity of 100%, the corresponding diagnostic specificities for MEGX and bilirubin from the first examination were 77 and 62%, respectively. These data show that consistently low MEGX test results < 10 micrograms/L, obtained 30 min after intravenous administration of lidocaine (1 mg/kg body weight), are a prognostically unfavorable sign in pediatric transplant candidates.     

污水中氰化物的微生物降解作用

金矿生产过程所产生合氰污水中含有不同类型的氰化物．从金矿合氰污水中分离、驯化、培养了节细菌、白曲霉菌、拟青霉菌．通过实验研究了它们对氰化物具有耐受能力与降解作用．在氰化物CN-浓度小于1000mg／L时能够生长、繁殖;CN-为2000mg／L时仍然存活．在pH＞7条件下,微生物对CN-有较强的降解能力．在96h内能把污水中的CN-（100mg／L时）降解为零.研究表明,微生物能够把CN-分解为CO2和NH3,从而彻底脱出除氰化物．微生物降解氰化物是有效方法．