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1.
按照《船舶压载水和沉积物控制和管理国际公约》对岸基测试试验的要求,采用准平行光束仪对8种淡水藻辐射,黑暗环境培养5d,确定剂量反应关系,研究紫外线对它们的灭活效果及特点.结果表明,紫外线法对梅尼小环藻、谷皮菱形藻、小球衣藻和铜绿微囊藻具有一定的灭活效果,灭活率随着紫外线剂量的增加而提高;小剂量的紫外线会刺激镰形纤维藻和斜生栅藻细胞生长,在剂量大于300 mJ·cm-2时藻细胞的数量开始缓慢减少;剂量小于400 mJ·cm-2时对钝脆杆藻和卵形隐藻没有灭活效果.紫外线对淡水藻的灭活效果较差.藻细胞个体大小不是影响紫外线灭活效果的原因,藻的种类、藻细胞壁的有无及其成分的不同可能是造成不同灭活效果的原因.  相似文献   

2.
摘要: 目的 探究工艺处理对不同病毒的灭活效果及清除能力,为清除动物源性产品中病毒污染提供有效的灭活 方法。方法 选用新城疫病毒,人轮状病毒,伪狂犬病毒,猪细小病毒四种病毒作为指示病毒,加入所选材料中,经 草酸和盐酸的清除工艺后,计算病毒初始及处理后的病毒滴度,总结工艺灭活效果。结果 经过 10% 草酸 1. 5 h 处理后,病毒滴度明显下降,但并未完全灭活; 继续经过 10% 盐酸处理 1h 后,病毒滴度下降到零,病毒完全灭活。 结论 该酸处理工艺可以有效地清除病毒,达到良好的灭活效果,保证产品的安全性。  相似文献   

3.
以铜绿微囊藻为研究对象,考察了紫外线照射对铜绿微囊藻的灭活效果及光合活性的影响,并研究了经紫外线照射后藻溶液水质的变化情况.结果表明,紫外线对铜绿微囊藻的灭活效果随着紫外线剂量的增大而提高,而光合活性随着紫外线剂量的增加呈指数下降;在藻浓度为35×108个.L-1条件下,91.8mJ.cm-2的紫外线剂量即可对其产生有效的抑制作用,紫外线照射时间10min是抑制藻类生长的最佳时间;藻的浓度对紫外线灭活藻有一定影响,紫外线对高浓度藻灭活效果明显;紫外线照射对藻液的UV254影响较小,但藻液的DOC(溶解性有机碳)随着紫外线剂量的增加呈现先增大后降低的趋势.  相似文献   

4.
把两株酿酒酵母(saccharomyces cerevisiae)S_1、S_2的原生质体分别用紫外线(U.V)和碘乙酰胺灭活或只用紫外线灭活,经PEG诱导融合后,在完全培养基上得到了融合子。融合频率为(0.98-2.13)×10~(-7)。融合子的细胞形态、DNA含量等都和亲株有明显差别,并在生产特性上有某些改进。  相似文献   

5.
采用3种不同方法对北京工商大学中水站污泥进行了前处理,采用原子吸收光谱法测定铅和镉的含量,实验结果表明:由于干法消解温度较高,可以消解的更加完全,其效果要好于湿法消解,但干法消解时间过长则可能引起重金属成分的挥发损失,降低消解效果。  相似文献   

6.
饮用水中隐孢子虫的紫外线灭活   总被引:3,自引:0,他引:3  
介绍了隐孢子虫的生活形态以及隐孢子虫病的传播情况,通过对欧美等国爆发的隐孢子虫病的分析,指出传统的水处理工艺不能有效地去除侵入水中的隐孢子虫卵囊,应该对现有的处理系统进行改造.紫外线灭活隐孢子虫研究的进展情况表明,紫外线对其的灭活率达到99%和99.99%时,紫外线剂量分别为11mJ/cm^2和19mJ/cm^2.最后建议确定简单合理的检测方法,并加强紫外线灭活污水中隐孢子虫的研究.  相似文献   

7.
<正> 小鼠仙台毒感染曾打算用灭活病毒疫苗,用温度敏感的变种病毒及用有佐剂的灭活苗来予防。但很少研究仙台毒疫苗对大鼠的效力及安全性。上文中曾报导仙台毒用吐温80,乙醚,福马林及紫外线结合处理灭活后可使鼠产生血清抗体并由接种疫苗的母鼠把抗体转给其仔代。本文报导这种疫苗的效力。研究用的大鼠为该所繁殖的五周令Wistar大鼠,公母均有。种鼠群(用检查淘汰种鼠血清学监测的方法来证明)无仙台  相似文献   

8.
干法灰化-ICP-AES法测定奶粉中的磷   总被引:1,自引:0,他引:1  
用干法灰化法处理奶粉样品,电感耦合等离子体发射光谱法(ICP-AES)测定了样品中磷的含量,并研究了干法灰化最佳温度和仪器最佳工作条件.本法与其他方法比较,处理样品方法简单、快速,测定结果准确可靠,方法检出限为0.0505 mg/L,回收率为95.8%—105.2%.  相似文献   

9.
以配置的水样为研究对象考察了氯与二氧化氯单独及联合灭活大肠杆菌和细菌总数的效果,用Berenbaum公式判断了两种消毒剂联合作用的性质.结果表明,氯2.00mg/L作用30 min可灭活试验水样中大肠杆菌6.18个数量级,二氧化氯0.30 mg/L作用15min、1.50mg/L氯和0.20 mg/L二氧化氯联合作用10 min可以灭活试验水样中大肠杆菌7.18个数量级(100%灭活);2.00 mg/L氯单独作用30 min、0.30 mg/L二氧化氯单独作用15 min、1.50 mg/L氯和0.20 mg/L二氧化氯联合作用10min可将水样中的细菌100%灭活.用Berenbaum公式计算得出氯与二氧化氯联合消毒灭活水样中大肠杆菌时质量浓度比为0.39,灭活水样中细菌总数时的质量浓度比为0.85,因此氯与二氧化氯联合消毒对大肠杆菌和细菌总数具有协同灭活作用.  相似文献   

10.
王亚萍  杨兰 《甘肃科技纵横》2004,33(4):178-178,148
目的:研究各种临床消毒方法对藻酸盐印模的消毒效果。方法:选用1500mg/L的NaClO消毒液、2%中性强化戊二醛消毒液和臭氧消毒表面污染有乙肝病毒血清的藻酸盐印模进行浸泡消毒,检测消毒效果。结果:1500mg/L的NaClO消毒液浸泡消毒10min可完全灭活HBsAg;2%中性强化戊二醛消毒液浸泡消毒40min可完全灭活HbsAg,臭氧消毒60min仍无效。结论:1500mg/L的NaClO、2%中性强化戊二醛消毒液均可灭活HBsAg。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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