关于室内甲醛污染的调查

近年来，甲醛对人体健康的影响越来越引起人们的关注。大量文献记载，甲醛对人体健康的影响主要表现在嗅觉异常、刺激、过敏、肺功能异常、肝功能异常和免疫功能异常等方面。其浓度在每立方米空气中达到0．06—0．07mg／m^3时，儿童就会发生轻微气喘。当室内空气中甲醛含量为0．11mg/m^3时，就有异味和不适感；达到0．5mg／m^3时，可刺激眼睛，引起流泪；达到0．6mg／m^3，可引起咽喉不适或疼痛。浓度更高时，可引起恶心呕吐，咳嗽胸闷，气喘甚至肺水肿；达到30mg／m^3时，会立即致人死亡。目前，国内外对甲醛的调查研究已越来越广泛，越来越深入。我们利用2个月的时间，在邯郸市随机挑选了100户家庭，对不同类型的建筑物，不同质地的装修材料．不同楼层．进行相同的测定。     

重庆住宅室内空气中甲醛污染调查

为了了解和掌握重庆市新装修后住宅室内空气中甲醛浓度水平，对新装修后住宅室内空气进行实测和入户调查，结果表明：室内空气中甲醛平均浓度为0．22mg／m^3，超标率高达76．3％．在装修完成后3个月时甲醛浓度最高，装修完成后6个月时甲醛浓度最低．这说明重庆新装修住宅室内空气中普遍存在甲醛污染，应引起高度关注．     

臭氧消毒方法在实验动物屏障环境运行中的应用

目的研究正确使用臭氧对实验动物屏障环境进行消毒的方法和浓度，达到既保证消毒效果、又保证屏障环境内实验动物及工作人员安全的目的。方法控制2个臭氧浓度在0．32mg／m3和0．21mg／m3的屏障环境，进行消毒效果对比实验；选用清洁级ICR小鼠进行正常的生产繁殖，观察不同浓度的臭氧消毒对小鼠产仔率、肺功能的影响，以及对空气中氨气浓度的影响。结果臭氧浓度为0．21mg／m^3和0．32mg／m^3时都达到了灭菌效果；臭氧浓度为0．32mg／m^3时动物的死胎率、肺部病变例数与对照组和臭氧浓度为0．21mg／m^3组有显著差异，氨气浓度下降85％；臭氧浓度为0．21mg／m^3时动物的死胎率、肺部病变例数与对照组没有显著差异，氨气浓度下降75％。结论实验动物屏障环境动态运行时，臭氧消毒最适合的剂量为0．21mg／m^3。     

甲醛对果蝇的伤害及维生素C的保护作用研究

以果蝇为材料,探讨了甲醛对果蝇的伤害作用以及维生素C的保护作用.分析了在甲醛和维生素C的影响下,果蝇子代的生存率、幼虫体内的几种主要物质(如核酸和蛋白质)含量的变化动态以及细胞内产生的微核数等.结果发现,随着培养基中甲醛浓度的升高,果蝇子代数量逐渐减少;幼虫体内的蛋白质含量有所降低,核酸含量变化不明显,细胞内微核数量增高.而维生素C对甲醛的毒害存在显著的拮抗效应.当培养多代后,这些效应逐渐减轻.     

松墨天牛致病菌葡萄曲霉安全性研究

松墨天牛生葡萄曲霉Aspergillus vitis分生孢子对水蚤、果蝇、鲤鱼和对小白鼠经口、经皮、吸入急性毒性试验结果表明：水蚤在20mg／L浓度下72h死亡率23.3％;果蝇在浓度为21mg／L下72h死亡率15．0％;鲤鱼在浓度为22mg／L时72h死亡率4．0％。用3种途径对小鼠的试验表明,小鼠无死亡现象发生,小鼠的体重也无明显影响。该葡萄曲霉对这些实验动物表现为低毒或微毒。     

空气中微量甲醛的快速检测方法的研究

研制了一种能够测定空气中低浓度甲醛的检测方法。其载体为(80～100)目的活化硅胶;玻璃管内径为(2．0～2．5)nm;吸附显色剂为硅胶、稀硫酸和显色剂A的混合物。对空气进行测定的采样条件为：采气速度0．02L／min,采样量0．1L。经初步试验,该检测管变色程度与甲醛浓度的相关性(r=0．9991);检测重现性(不同浓度测定的变异系数小于5％);灵敏度(最低显色浓度为0．1mg／m^3)可对室内环境中的甲醛浓度进行快速检测,操作简便,易于携带和使用,适合一般家庭的使用。     

植物延绿节水复壮剂在草坪中应用效果

以叶片含水量、土壤含水量、植物长势、叶绿素等为指标,分析施用0.2kg／m^2、0.4kg／m^2、0.6kg／m^2等不同浓度的复壮剂（NSR）对高羊茅（Festuca arundinacea Schreb．）及草地早熟禾（Poa pratensis L．）草坪产生的节水与延绿效果。结果表明：施用NSR对草坪植物叶片内叶绿素含量具有一定影响。施用NSR用量控制在0.2kg／m^2可以更好地减缓植物叶片中叶绿素含量的流失。与对照组相比较,NSR对植物叶片含水量、土壤含水量等方面影响并不显著,说明NSR不能有效地抑制土壤水分蒸发速率。     

黑潮区颗粒有机碳和生物硅输出的^234Th／^238U不平衡示踪

对东海陆架外黑潮区颗粒有机碳（POC）和生物硅（bSiO2）的研究表明：台湾东北部黑潮主流真光层（100m）POC和bSi02的平均浓度分别为3．31μmol／L和0．68μmol／L;^234Th／^238U不平衡法获得POC和bSi02的输出通量分别为3．7mmol／（m^2·d）和1．6mmol／（m^2·d）．黑潮沿东海陆架北进过程中,POC和bSiO2的含量及输出通量均呈增加趋势．位于日本西南的黑潮主流中,POC和bSiO2的平均浓度分别为3．85μmol／L和2．63μmol／L,输出通量分别为6．7mmol／（m^2·d）和4．0mmol／（m^2·d）．黑潮与陆架水形成的锋面区,POC和bSiO2浓度均高于黑潮主流．     

有膜法电化学合成丁二酸的研究

研究了有膜法电化学合成丁二酸的电解过程，探讨了硫酸浓度、电流密度、初始马来酸浓度、温度对转化率、电流效率、电能的影响，获得适宜的阴极电解条件为硫酸浓度0．6—0．9kmol／m^3，电流密度0．15A／cm^2，马来酸浓度1．0-1．5kmol／m^3，温度50-55℃。     

硫酸铈诱导果蝇氧化应激及细胞凋亡的研究

本实验主要研究了稀土硫酸铈（Ce（SO4）2）对果蝇氧化应激生物标记物和细胞凋亡的影响.果蝇培养在不同质量浓度（1,4,16,64,256,1 024 mg/L）的硫酸铈培养基中,分别测定其SOD,CAT和脂质过氧化产物（即MDA含量）,同时用彗星电泳和体外切割DNA实验来检测果蝇细胞中DNA损伤程度,用DNA Laddering法和TUNEL法测定稀土元素Ce对果蝇细胞凋亡的影响.与对照组相比,当Ce（SO4）2质量浓度低于16 mg/L时,果蝇体内SOD和CAT活性显著增加,MDA含量变化不明显;而当Ce（SO4）2质量浓度高于16 mg/L时,SOD和CAT活性明显下降,MDA含量上升.彗星电泳的结果表现为随着硫酸铈剂量的递增,果蝇中肠细胞的彗星率、彗星尾长和Olive尾矩增加,并表现为明显的剂量效应关系.果蝇体外实验结果表明,硫酸铈能打断DNA,使其片段化;同时,TUNEL结果显示果蝇中肠细胞呈现凋亡细胞的特征性蓝绿色颗粒,但DNA琼脂糖电泳没有表现出细胞凋亡特征性的梯形条带图谱.硫酸铈诱导果蝇的氧化应激可以使果蝇中肠细胞SOD和CAT活性降低,MDA含量上升,使中肠细胞出现凋亡特征.由此推断,硫酸铈可诱导果蝇细胞中遗传物质的损伤,对果蝇有一定的氧化毒性和遗传毒性作用．     

Markedness and its Interpretation in Language Use

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the