低压蒸汽锅炉水质控制

从锅炉给水和锅炉炉水2个方面,阐明了如何对低压蒸汽锅炉水质进行控制,从而确保低压蒸汽锅炉的安全、经济运行。     

人胰岛素酶联免疫分析法的建立

采用两株抗胰岛素单克隆抗体,一株包被聚苯乙烯板、另一株标记辣根过氧化物酶,建立了测定人胰岛素的双抗体夹心酶联免疫分析法。方法学研究表明,本方法的灵敏度为1.7mIU/L,曲线范围5~160mIU/L,批内、批间变异系数分别小于11%、15%,回收率96.4%~111.1%;高浓度胰岛素血清样品系列倍比稀释后测定,测定值与稀释度呈线性相关,相关系数0.998;38例健康人血清样品测定值为3.6~10.8mIU/L。该方法与人胰岛素放射免疫分析法测定结果的相关性良好,r=0.97。     

人参皂苷Rb1单克隆抗体的制备与鉴定

用人参皂苷Rb1分别与牛血清白蛋白(BSA)和卵清蛋白(OVA)反应合成了交联抗原GRb1-BSA(GRb1与BSA的结合比为10∶1)和GRb1-OVA(GRb1与OVA的结合比为8∶1)。以GRb1-BSA为免疫原,分5次免疫3只BALB/C小鼠,取免疫脾细胞与小鼠骨髓瘤细胞进行融合,Hat筛选,有限稀释法克隆。建立分泌单克隆抗体的杂交瘤细胞系。采用ELISA(酶联免疫吸附测定)间接法和竞争法检测抗体的特异性。结果获得了一只小鼠分泌抗体效价达1∶16000,并获得两株分泌GRb1的单克隆抗体的细胞系,分别命名为1F7和1G3,单抗检测显示在0.01~1μg/mL呈线性关系,GRb1的检测范围达50~350 ng/mL,两株单抗针对相同的抗原决定簇,制备的单克隆抗体可用于GRb1含量的检测和分离。     

水库水有机污染物遗传毒性的研究简

为研究水库水经国内常规给水处理工艺的各阶段出水中有机提取物对细胞DNA损伤的情况,于8月和1月取水库水作为原水,设定采集4个水样：原水（A）、经混凝沉淀后的沉后水（B）、滤后水（C）和经氯消毒的出水（D）。提取水样中的有机物配成不同浓度溶液,喂食小白鼠,取小白鼠脾脏细胞做彗星实验。结果无论在枯水期还是丰水期,水处理工艺各阶段出水对DNA都有不同程度的损伤,损伤程度顺序：A〉B〉D〉C;丰水期水样对DNA损伤程度高于枯水期水样对DNA的损伤。结果表明,水库水中的有机物污染物具有一定的遗传毒性,常规给水处理工艺对遗传毒性有削减作用,但不能消除。加氯消毒增加了水库水的遗传毒性。     

中压锅炉煤粉经济细度的确定

通过对中国长城铝业公司热力厂８台中压煤粉锅炉燃煤特性的分析，煤粉经济细度的计算以及球磨机运行实践的阐述，确定了本厂锅炉的煤粉经济细度，对企业煤粉锅炉安全经济运行，节能降耗具有一定的指导意义。     

豆腐果甙对小鼠脑谷氨酸脱羧酶和γ-氨基丁酸转氨酶活性的影响

豆腐果甙(Helicid,简称Hel)系中国科学院昆明植物研究所从山龙眼科萝卜树(Heliciaerratica Hook)的果实中提取的一种成分。其化学名为4’-甲酰基苯基-β-D-吡喃阿洛糖甙(4’-formyl-pheny-β-allopyranoside)。Hel有镇静、催眠和一定的抗惊厥作用,亦可使氨基硫脲(TSC)降低的小鼠脑中γ-氨基丁酸(GABA)水平恢复正常。为此,我们用放射性酶测     

BACTERIAL MUTAGENICITY OF DICYCLOPENTA-FUSED PYRENE CONGENERS IN FVT-PYROLYSATES: PARTIAL COMBUSTION EXHAUST MIMICS

The mutagenicity response of well-characterized flash vacuum thermolysis (FVT) pyrolysates that contain cyclopenta[cd]pyrene (1) and 1-ethynylpyrene (1b) (pyrolysate I), the dicyclopentapyrene congeners dicyclopenta[cd,mn]- (2), dicyclopenta[cd,fg]- (3), or dicyclopenta[cd,jk]pyrene (4) and their related bis-ethynyl- (2b–4b) and monocyclopenta-ethynylpyrene (2a–4a) analogues (pyrolysates II–IV, respectively), or cyclopenta[cd]- (1) and the three dicyclopentapyrenes (2–4) (pyrolysate V), respectively, was assessed using the standard protocol outlined by Ames et al. (Salmonella typhimurium strain TA98 ± S9-mix 4% (v/v)). It is shown that the mutagenic activity of the pyrolysates deviates from the weighed sum of the activity of the individual pyrolysate constituents. Hence, FVT-pyrolysates are proposed as model mixtures, that is, as partial combustion exhaust mimics, to establish and evaluate interactions (additive, synergistic, or antagonistic effects) that may occur among the constituents and affect the global mutagenicity response.     

Development of an analytical protocol for detecting antibiotic residues in various foods

Medicines such as antibiotics and hormones have been widely used for treating diseases in animals. As more antibiotics are needed to prevent various diseases that occur, not only in domestic animals, but also in imported livestock, a quick and robust analytical method is required for detecting antibiotic residues. In this study, agricultural and fishery products, including beef (n = 148), pork (n = 78), chicken (n = 88), eel (n = 70), flatfish (n = 17), armorclad rockfish (n = 18), sea bream (n = 18), perch (n = 18), and oyster (n = 4) were obtained from local markets in different areas of Korea. A total of 13 antibiotics, including tetracycline, macrolide, penicillin, aminoglycoside, polyester, peptide, and chloramphenicol types, were analyzed by a microbial assay and high performance liquid chromatography (HPLC). In the microbial assay, 34 of the 459 screened samples had possible antibiotic residues. The antibiotic concentrations of the 34 samples were analyzed using HPLC with UV and fluorescence detection. The levels of oxytetracycline in pork and eel were 0.01 and 0.05 mg/kg, respectively. In eel and oyster, the concentrations of ampicillin were 0.4 and 0.32 mg/kg, respectively. In beef, the concentration of tylosin was 0.05 mg/kg. The levels of oxytetracycline and tylosin were below the Korean Food Code’s recommended maximum residue limit (MRL). A maximum residue limit for ampicillin in fishery products, however, has not been established in Korea. These data indicate that an MRL for ampicillin should be set for sea foods and regulated by the Korean authorities.     

The determination of l-carnitine in several food samples

We designed this study to re-validate some methodological parameters of the radio-enzymatic assay, including phenomena of residual, non-carnitine radioactivity present in some assay mixtures of food samples. The second part of the paper presents l-carnitine concentrations (total-, free- and acyl-carnitine) in a wide range of food samples of animal and plant origin.