层流手术室术中浸血盐水细菌含量研究与分析

目的研究层流手术室术中影响浸血盐水含菌的因素和适宜更换的时间。方法实验室定量接种法对Ⅰ、Ⅱ类手术各50例术中浸血盐水,分别于手术开始(0min)至结束每隔30min采样计数盐水含菌量,同时采用平板暴露法对空气进行采样,计数相应时间的空气含菌量。结果空气和盐水两者含菌量无明显相关性(r=0.037,P>0.05);两类手术盐水含菌量90min前各时间点对比,差异均无统计学意义(P>0.05);而90min以后盐水含菌量均明显上升,同一时点Ⅱ类手术盐水含菌量显著高于Ⅰ类手术(P<0.05)。结论影响层流手术室术中浸血盐水含菌量的因素是手术种类而不是空气含菌量。手术开始后90min是更换盐水的最佳时间。

术中早期预输高渗盐水预防前列腺电切综合征的临床可行性研究

目的探讨术中早期预输高渗盐水在预防前列腺电切综合征中的效果。方法选取2010年6月~2012年6月于本院进行前列腺电切术治疗的166例患者为研究对象,将其随机分为对照组(常规治疗组)和观察组(术中早期预输高渗盐水组)各83例,然后将两组患者的前列腺电切综合征发生率及术前、开始手术后的30min、60min的循环系统和血Na+、K+、Cl-、糖、血红蛋白指标进行比较。结果观察组的前列腺电切综合征发生率低于对照组,血Na+、Cl-均高于对照组,有显著性差异(P【0.01)。结论术中早期预输高渗盐水可有效降低前列腺电切综合征的发生率。

传统式手术中浸血盐水细菌含量分析

[目的]研究传统手术中影响浸血盐水含菌的因素和适宜更换时间。[方法]实验室定量接种法对Ⅰ类、Ⅱ类手术共60例术中浸血盐水分别于手术开始至结束每隔20min采样计数盐水含菌量,同时采用平板暴露法对空气进行采样,计数相应时间的空气含菌量。[结果]空气和盐水两者含菌量无明显相关性(r=0.035,P>0.05);两类手术盐水含菌量80min前各时间点比较差异均无统计学意义(P>0.05),而80min以后盐水含菌量明显上升,同一时间点Ⅱ类手术盐水含菌量显著高于Ⅰ类手术(P<0.05)。[结论]影响传统式手术中浸血盐水含菌量的因素为手术种类,手术开始后80min是更换盐水的最佳时间。

利用天平和量筒测量盐水密度的误差分析

分析实验误差是一项重要的实验技能,分析实验误差有利于培养学生分析问题和解决问题的能力,有利于培养学生的创新能力和精益求精的品质。天平和量筒是初中物理中常用的测量工具,利用天平和量筒测量盐水的密度是初中物理的基础实验。从测量方法上分析实验误差,有助于理解和确定这个实验方案的合理性与否。

纯淡水南美白对虾养殖淡化环节的几点体会

1在小水体逐渐淡化或适应这是笔者连续养殖南美白对虾九年都成功的主要体会。在虾苗运来前1~2d把养殖池水质调节好,及时消毒,虾苗采用铁制大水箱、用氧气瓶充氧的方法运输,运输到本场后,铁制大水箱作为淡化工具,用气泵加软管的方式给虾苗充氧,淡化用水为水箱中原虾池水和本场预养虾池中消毒后的池水,根据每次淡化所设定的盐度（每天降低1个千分点）,首先将大水箱中盐水抽出一部分,然后加入淡水,

Impact of brine acidification on hatchability, survival and reproduction of Artemia parthenogenetica and Artemia franciscana in salt ponds, Bohai Bay, China

We studied the effect of pH （pH 5, 6, 7 and 8） on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay （BHB）, Artemiafranciscana from San Francisco Bay, and A. franciscana artificially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were significantly reduced when exposed to a culture medium at pH 5 for 18 d （P〈0.05）. The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order： juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6-8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidification has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franeiscana should be feasible at pH 7-8.

Freshening of the intermediate water of the South China Sea between the 1960s and the 1980s

Variation in intermediate water salinity in the South China Sea (SCS) between the 1960s and 1980s was studied using historical hydrographic data. The results demonstrate that the water was significantly fresher in the 1980s than in the 1960s, indicating that vertical mixing at intermediate water depth was reduced in the 1980s. This was partially because of the change of the SCS meridional overturning circulation (MOC) connecting local intermediate water with deep water. Data assimilation showed a 0.5Sv (1 Sv=10 6m 3/s) reduction in the strength of the MOC, which is about one third of the mean SCS MOC. Because the SCS MOC is linked to the Pacific Ocean, such an interdecadal variation in the intermediate water SCS may reflect anthropogenic climate change in the world ocean.

A Successful Microbound Diet for the Larval Culture of Chinese Shrimp Fenneropenaeus chinensis

A 13-day feeding trial was carried out to evaluate the effectiveness of a microbound diet for rearing the larvae of Chinese shrimp Fenneropenaeus chinensis in comparison with the live foods that consist of Isochrysis galbana, Chlorella vulgaris, Tetraselrnis chuii, rotifer （Brachionus plicatilis） and Arternia sp. Larvae of 0 to 13d post-hatch （dph） were reared in a temperature-controlled semi-open culture system and stocked at a density of 100 larvae L^-1 in tanks, each containing 50 L sterilized seawater with salinity 30-32. Larvae were manually fed either the live foods or the microbound diet 6 times per day. At 13 dph, the growth of the larvae fed on the microbound diet was approximately 84% of that fed on the live foods. The survival rate of the larvae fed on the microbound diet was 44.29% at 13dph, which was not significantly different from that of larvae fed on live foods （63.55%）. The body length and development index （DI） of the larvae fed on the microbound diet were always lower than those of larvae fed on live foods. However, the differences reached significant levels only at 11 and 13 dph （P〈 0.05）. The mean dry weight loss of the microbound diet was 9.2% after 90 min immersion in seawater, indicating that this diet has a good water stability. The microbound diet contains 52.23% crude protein and 10.27% lipid and is easy to prepare. These characteristics of the diet suggest good potentials for its successful use in the larviculture of other penaeid and fish species.

Properties of Belite-Rich Portland Cement and Concrete in China

Performances of belite-rich Portland cement, or HBC （high belite cement）, and the resultant concrete are introduced by comparing with that of alite based PC （Portland cement） and concrete. The comparison study of cement properties indicates that HBC possesses the properties of less water demand for normal consistency, better compatibility with water reducer, higher later age strength after 28-day under standard curing temperature of 20 ℃, unique strength gain under elevated curing temperatures of 38-70 ℃, lower hydration heat evolution and temperature rise, lower drying shrinkage and excellent resistance to sulphate attack. These results have been demonstrated by the comparison performance evaluation of concretes prepared by HBC and PC in terms of workability, physical mechanical properties and durability when making high performance high strength concrete and massive concrete.

Porosity Distribution Characteristics and Geological Analysis of Brine Storage Medium in the Qaidam Basin, Western China

Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. Pores in the brine storage medium act as storage space and transmission channels of underground brine. Therefore, the porosity of brine storage medium determines its ability to store brine. In this study, Mahai Salt Lake was used as the research area as a modern saline lake located in the north area of the Qaidam Basin. A total of 100 porosity samples were collected from eight sampling points in two profiles of the research area at sampling depths of 1.30–314.78 m. The porosity distribution characteristics and influencing factors in brine storage medium were analysed according to the measured porosity data. Based on analysis of the pore structure characteristics, the brine storage medium contains intercrystalline pores, unlike conventional freshwater storage mediums. Moreover, the primary salt rock is susceptible to dissolution by lighter brine, facilitating the formation of secondary porosity. Due to the formation of secondary pores, a porosity greater than 20% remains even at buried depths greater than 100 m. Based on the geological statistical analysis, due to the geographic location, salt formation time, and depositional environment, the porosity values of Mahai Salt Lake do not exhibit a wider distribution, but also show more extreme values than a nearby salt lake. Based on the porosity characteristics by depth, due to the presence of secondary pores, flooding, stratigraphic static pressure, and other factors, porosity shows fluctuations with increasing depth.

Measurement and Correlation of Partition Coefficients of Baicalin in EOPO/Salt Aqueous Two-Phase Systems

The partition coefficients of baicalin were measured in ethylene oxide and propylene oxide (EOPO)/salt aqueous two-phase systems at 298.15K. It was found that most of baicalin partitioned into EOPO-rich phase. The partition coefficients of baicalin varied from 10 to 120. The effect of various factors, including tie-line length, salt composition, molecular weight of EOPO, and solution pH, on the partition behavior was investigated in EOPO/salt systems. Furthermore the partition coefficients of baicalin were correlated using the modified Diamond-Hsu model. Good agreement with experimental data is obtained. The average relative deviations are less than 5.0%.

Nutrient and chlorophyll a anomaly in red-tide periods of 2003-2008 in Sishili Bay, China

Sishili Bay is the most important aquiculture and tourism area for the city of Yantai, China; however, red tides occurred frequently and have caused huge economic losses in this bay in recent years. To gain a better understanding of the local ecological environments in the bay, we conducted this research between 2003 and 2008 to analyze variations in nutrients and chlorophyll （chl-a） during high frequency red tide period （May to September）. The results show that the chl-a concentration increased from 2.70 in 2003 to 7.26 mg/m3 in 2008, while the concentration of total inorganic nitrogen （TIN） and silicate （SiO3-Si） increased lineally from 5.18 and 1.45 pmol/L in 2003 to 18.57 and 9.52 pmol/L in 2008, respectively, and the annual phosphate （PO4-P） varied between 0.15 and 0.46 μmol/L. Special attention was given to a red tide in August 2007 occurred when water temperature was high and nutrient concentrations increased sharply because of a heavy rainfall. Overall, the results show the P limitation in Sishili Bay, and reveal that red tides were caused by eutrophication from terrestrial inputs and local warm weather, particularly during rainy periods. Therefore, to control red tide, greater efforts should be made to reduce sewage discharges into Sishili Bay, particularly during rainfall seasons.

离子膜电解槽运行注意事项

总结了电解槽运行中盐水质量、阴阳极液浓度、槽温、电流密度、压差、反向电流等各项操作指标对离子膜性能的影响。

Application of nitrogen-fixing cyanobacteria in restoration of saline and alkaline soils of Songnen Plain in China

The salt-resistant nitrogen-fixing cyanobacteria 888 was experimentally applied to the reclamation of saline and alkali soil in Songnen Plain in China. The pH, electrical conductivity (EC) and sodium adsorption ratio (SAR) of different saline soils were studied and compared. Results show that different saline soils exhibit various physico-chemical properties. Saline-sodic soils in Songnen Plain are ameliorated by using nitrogen-fixing blue-green algae 888 in the experiment. It is indicated that cyanobacteria 888 can grow in saline and alkaline soils, and the conditions favorable for its growth are soil moisture of 50% and dry algae inoculation at 0.03 mg/cm2. The main actions of nitrogen-fixing cyanobacteria are keeping the adsorbability of rubber sheath for sodium, increasing the organic matter content of the soils and decreasing the pH and the degree of salinity in the soils. But the arid climate and soil depth are the main factors that limit the restoration of saline and alkaline soils.

A Preliminary Study on Cactus as Flocculants in Water Recycling from Moroccan Phosphates Schlamms

In this work we used a new organic biodegradable flocculants which is the cactus cladodes juice in order to recycle water from phosphate schlamms. This flocculants has enabled us to increase the settling velocity of the schlamms so consequently the water recycled degree. The study was conducted on an industrial sample of phosphates schlamms from Khouribga phosphates washing plant. The study was about the influence of concentration, pH, and velocity gradient with cactus extract leads to satisfactory results in term of settling decantation, and in water recycling degree which is 93%.

Development characteristics and quantitative prediction of reservoir fractures in the Chaoyanggou oil field

The Chaoyanggou oil field is a fractured low-permeability reservoir, where the distribution of oil and gas is controlled by the distribution and development of fractures.Based on outcrop, drilling core, thin section and log data, the development characteristics of fractures in this area are described.On this basis, the degree of fracture development was predicted by quantitative analysis of fracture strength and numerical simulation.The result shows that four groups of structural fractures, i.e., in near NS, and EW directions and in due NW and NE directions, were developed in the reservoir, with the nearly NS and EW fractures dominant, which are the along bedding decollement fractures formed by compressive folding action, while low angle shear fractures are related to thrusts.These fractures are mainly formed in the reversed tectonic stage at the end of the Mingshui formation during the Cretaceous period.The degree of fracture development is controlled by such factors as lithology, stratum thickness, faults, folds and depth.The fractures are developed with a clear zonation and are best developed in the northern zone, moderately developed towards the south and poorly developed in the middle zone.These prediction results are in good agreement with interpretation results from logs.

Improving endotracheal tube tolerance with intracufflidocaine: a meta-analysis of randomized controlled trials

Objective： The aim of this study was to compare the efficacy in alleviating the endotracheal tube related discomfort and the safetyof intracufflidocaine （in different forms） with air and/or normal saline （NS） during general anesthesia with tracheal intubation. Methods： Cochrane Central Register of Controlled Trials, PubMed and Embase were searched for relevant studies. Thirteen randomized, controlled trials involving 1 010 patients were ultimately identified. A meta-analysis of all randomized controlled trials fulfilling the predefined criteria was performed. Random-effect model and subgroup studies were used when significant heterogeneity existed among those trials. Results： Compared with air and NS, intracufflidocaine could significantly alleviate the severity of sore throat at different time points （15min, 30min, lh, 2h, 3h, 6h, 12h and 24h aiter extubation） and the occurrence of cough, restlessness, postoperative nausea and vomiting, dysphonia and hoarseness. Besides intracufflidocaine brought about a significant prolongation of spontaneous ventilation time. It was worth mentioning that, compared withlidocaine or its hydrochloride form, alkalinized lidocainewas much more efficient in reducing the severity of sore throat and prolonging spontaneous ventilation time. Conclusion： The present meta-analysis indicates that intracuttlidocaine can significantly improve endotracheal tube tolerance and this improvement can be strengthened by alkalinization of lidocaine.

Relationship between Water and Vegetation in the Ejina Delta

Water is the foundation of an arid ecological system, as the quantity and quality of surface water and groundwater determine its structure and function. The study on the relationship between water and ecosystem is the basis of ecosystem protection. Taking the Ejina delta, an extremely arid area located downstream of the Heihe River in northwestern China, as an example, this article gives an overviewe of the study in three aspects: (1) the groundwater table and salinity dynamics and their driving factors, (2) the groundwater depth and salt threshold of natural vegetation ecosystem, and (3) the impact evaluation of ecological flow control on Ejina natural vegetation. The authors point out the importance of the research into the relation between water and ecosystem and its key difficulties and weakness, and put forward strategies for promoting the study processes.

Coupling relation between water and salt in irrigation area on a catchments scale

Water resource is the important factor for sustainable development in Weigan River catchments in western China. Based on ecological hydrology principles, the coupling relation between water and salt is monitored and analyzed. The water quality for irrigation in oasis ecosystem has a larger variable range in arid area, which depending on the input water resource and underground water mineralization degree and water chemical component on the catchments scale, the water and salt coupling is decided by the climate condition and soil feature and vegetation characteristics as well as human activity. Meanwhile, temporal and spatial change between water and salt is quite complicated. The environmental management should be paid attention to considering in irrigation area in the catchments.