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Search Results: 1 - 10 of 17758 matches for " Physical and chemical conditions "
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Aquatic macroinvertebrates of Batalha river reservoir for water captation and supply of the city of Bauru, SP, Brazil
Fabio Laurindo da Silva,Jandira Liria Biscalquini Talamoni,Gabriel Lucas Bochini,Sonia Silveira Ruiz
Ambiente e água : An Interdisciplinary Journal of Applied Science , 2009,
Abstract: In this study the composition and diversity of aquatic macroinvertebrates were evaluated in the reservoir of water captation of Batalha river, for treatment and supplying of the city of Bauru. The samples were made in dry (from June to August/2005) and rainy (from December/2005 to February/2006) seasons. We analyzed and identified 840 organisms belonging to 8 taxa (8 taxa in dry season and 4 in rainy season). The system presented low abundance and diversity of macroinvertebrates probably in response to water quality and physical and chemical variations in the characteristics of water associated with the occurrence of rain.
Efecto del secado al sol sobre la calidad del grano fermentado de cacao
Agronomía Tropical , 2004,
Abstract: the objective of this research was to study the effect of certain variables inherent to the natural sun drying process of cocoa, theobroma cacao l., on quality physical indexes and on chemical characteristics of fermented seeds from cumboto locality, aragua state. lotsof plants, consisting of mixed criollo and forastero cocoa types, fermented for 4 days in a trinitarian type fermentor, were dried on a cemented surface of smooth, rugged and intermediate (traditional) textures, with turning over of seeds every 1 and 0.5 hour for 4 days and without turning over. color, shell, seeds with deficient fermentation, split seeds and multiple seeds percentages, as well as total titratable acidity, volatile acidity, ph and tannins were determined for dry cocoa samples. humidity was also analyzed after 0, 3 and 4 days of drying. results showed that color did not vary when drying conditions were modified. on the other hand, an increase of split seed percentages and a decrease of shell and multiple seed percentages were detected when roughness of surface and turning over increased. it was also observed that chemical characteristics were no affected when drying conditions were modified.
Possible Signs of Life on the Planet Venus  [PDF]
Leonid V. Ksanfomality
International Journal of Astronomy and Astrophysics (IJAA) , 2013, DOI: 10.4236/ijaa.2013.31007
Abstract:

It is possible, the question on the existence of extraterrestrial life will be answered not as a result of its search for in other worlds removed by distances of dozens of parsecs but on the surface of Venus, i.e., of the nearest planet of the Solar system. The search for “habitable zones” in extrasolar planetary systems is based on the postulate on “normal” physical conditions, i.e., the pressure, temperature, and maybe atmospheric composition similar to those on Earth. But could not such an approach be a kind of “terrestrial chauvinism”? Considering the conditions on Venus as a possible analogue of physical conditions on low-orbiting exoplanets of the “super-Earths” type, a new analysis of Venusian surface panoramas’ details has been made. These images were produced by the VENERA landers in 1975 and 1982. A few relatively large objects were found with size ranging from a decimeter to half meter and with unusual morphology. The objects were observed in some images, but were absent in the other or altered their shape. The article presents the obtained results and analyzes the evidence of reality of these objects.

The Spatial Variation Characteristics of Physical Conditions of College Students in Jiangsu Province  [PDF]
Bo Chen, Dongjin Xian, Yuhao Gu
Applied Mathematics (AM) , 2017, DOI: 10.4236/am.2017.86068
Abstract: As an important component of national talent resources, the physical conditions of college students appear to be particularly important. Based on geographic information system platform of ArcGIS, this paper builds database to make a statistical analysis on the physical conditions of college students in Jiangsu province in the years of 2012 to 2016, using the analysis function and graphics. The conclusions: 1) The students’ physique conditions in Jiangsu province is in an overall downward trend; 2) There are differences between the male and female college students’ physical changes; 3) In view of the college students’ physical deterioration degree of agglomeration, different areas should adopt effective measures to strengthen students’ physique.
Physical-Chemical Conditions for Mobilization of Gold in the Mobin Gold Deposit, Southwest Hunan
漠滨金矿成矿物理化学条件的水—岩反应实验研究

GU Li,DAI Ta-gen,
谷俐
,戴塔根

地球学报 , 2003,
Abstract: 以漠滨金矿围岩地球化学特征和矿物流体包裹体组成为基础,模拟特定体系水-岩相互作用实验,研究结果表明,漠滨金矿的成矿元素Au主要源于赋矿围岩--板溪群五强溪组一套浅变质碎屑砂岩、砂质板岩和凝灰质板岩。Cl^-在中低温热液体系中能与Au形成稳定络合物的形式进行运移,因此Cl^-在该区Au成矿过程中起着相当重要的作用。成矿热液流体中Au主要以金硫、金氯络合物形式在溶液中迁移,阴离子∑S、Cl^-对金的活化、迁移及沉淀起主导作用。溶液中硫氯离子浓度、溶液酸碱度及反应温度是金活化、迁移及沉淀的决定性因素。
贮藏条件对湿热处理锥栗淀粉理化特性的影响
谢涛
- , 2015, DOI: 10.13982/j.mfst.1673-9078.2015.4.033
Abstract: 采用湿热法制得了锥栗重结晶淀粉,研究了贮藏条件对其理化特性的影响。结果表明:在4 ℃贮藏时,对重结晶淀粉体外消化动力学参数的影响很显著,能形成更多的抗性淀粉,第14天平均聚合度达到最大,晶型从贮藏0 d的A型,依次转变为第3 d、7 d的V型,第14 d、21 d的B型,相对结晶度变化非常显著;在25 ℃贮藏时对体外消化动力学参数的影响也较大,能形成更多的快速消化淀粉,第3天平均聚合度达到最大,晶型保持A型,相对结晶度变化不明显,仅出现低温熔融区,与4 ℃贮藏时相比,其熔融焓降低较多、熔融峰温度差降低更显著;在4/25 ℃贮藏时,对体外消化动力学参数的影响也很显著,能形成更多的缓慢消化淀粉,前7 d内平均聚合度增加较快,晶型从贮藏0 d的A型依次转变为第3 d的V型、第7 d和第14 d的B型、第21 d的V型,相对结晶度变化较快,高温熔融区的峰值温度和终止温度较之4 ℃贮藏时降低较多。
Starch from Castanea henryi was recrystallized by heat-moisture treatment; in addition, the effect of different storage conditions on the physical and chemical properties of recrystallized starch was studied. Storage at 4 ℃ was observed to exert a significant influence on the in vitro digestion kinetic parameters of recrystallized starch; in addition, storage at this temperature resulted in the formation of starch with greater resistance, with the average degree of polymerization reaching the maximum limit on the 14th day. The type of crystal showed a gradual change from type A (on day 0) to type V on the 3rd and 7th day, and type B on the 14th and 21st day, with significant alterations in the relative crystallinity. Storage at 25 ℃ also had a substantial effect on the in vitro digestion kinetic parameters, resulting in the formation of starch that could be digested faster. The maximum average degree of polymerization was achieved on day 3; the crystal type from day 0 (type A) was retained over time, and the changes in relative crystallinity were not obvious, excluding the appearance of a low-temperature melting zone. The melting enthalpy of crystallized starch stored at 25 ℃ was substantially reduced compared to that stored at 4 ℃; in addition, the reduction in melting peak temperature was observed to be more prominent. Storage at 4/25 ℃ also had a significant effect on the in vitro digestion kinetic parameters, resulting in the formation of starch that was slowly digested. This resulted in a relatively rapid increase in the average degree of polymerization up to the 7th day. The crystal type was altered from type A on day 0 to type V on the day 3, type B on the 7th and 14th days, and type V on the 21st day. Rapid changes in relative crystallinity were observed. In addition, the peak and conclusion temperatures of the high temperature melting zone decreased by large amounts compared to the 4 ℃ storage condition.
Physico-Chemical Assessment of Euphrates Riverbetween Heet and Ramadi Cities, Iraq  [PDF]
Emad A. Al-Heety, Ahamed M. Turky, Eethar M. Al-Othman
Journal of Water Resource and Protection (JWARP) , 2011, DOI: 10.4236/jwarp.2011.311091
Abstract: The physico-chemical parameters of Euphrates River water were studied between Heet and Ramadi cities during November 2008 to June 2009. Water were samples collected from eleven stations and analyzed for Temperature, Turbidity, Electrical conductivity (EC), Total suspended solids (TSS), pH, Total dissolved salts (TDS), Dissolved oxygen (DO), Biochemical oxygen demand (BOD), Calcium, Potassium, Sodium, Sulphate, Phosphate, Bicarbonates, Chloride, Nitrate and Total hardness. The observed values of these physico-chemical parameters were compared with WHO standards. Some parameters (Turbidity, TSS, TDS, BOD, Calcium, Sodium and Total hardness) exceeded the permissible limits of WHO standards, while other parameters were within the permissible limits. Statistical studies have been carried out by calculating correlation coefficients between different pairs of parameters. Monthly and spatial variations of physico-chemical parameters were investigated.
Variations in the Water Quality of an Urban River in Nigeria  [PDF]
F. A. Oginni
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2013, DOI: 10.4236/cweee.2013.22B014
Abstract: Sango-Ota is the industrial nerve centre of Ogun State in Nigeria. River Atuara is an urbanized river in this town. The aim of this study is to assess the quality of water in the river along its 13 km urbanized stretch within Owode – Ota and Gbenga quarters of Sango – Ota in Ogun State, Nigeria. A study of some physical and chemical analysis was carried out to determine the level of pollution in the river. Total Dissolved Solids, TDS, pH, Colour and Temperature measurements were obtained for nine locations on the 21 km river stretch. Laboratory analyses were carried out at 4 locations along the water course for the following parameters: pH, Conductivity, Turbidity, DO, BOD, COD, TDS, TSS. Others include Phosphate, Chloride, Nitrate, Sulphate, Cadmium, Lead, Iron, Copper, Zinc, and Nickel. Results indicate that the water quality reduces downstream of the urbanized stretch. Some of the level of heavy metals in the river calls for concern. At Owode, the lead content of 0.11 mg/L is too high compared to a maximum of 0.01 mg/l permissible, which can cause cancer. This can interfere with Vitamin D metabolism, and can affect mental development in infants. It is toxic to the central and peripheral nervous systems. Cadmium is below 0.002 which is just below the 0.003 mg/l permitted in Nigeria. Nickel content was 0.046 mg/l between Owode and Ewupe and this is above the maximum permissible level of 0.02 for Nigeria. This has the possibility of carcinogenic health impact. Owode and Ewupe have greater industrial impacts than the other two locations, Igboloye and Gbenga. The trends of each of the 21 parameters from the urbanized stretch of the river have been observed to follow a pattern that can be categorized as similar, mirrored, somersault and composite of mirrored and somersault. More studies were recommended in this direction as well as in determining the locations of factories and industries contributing to the pollution level around Ewupe and their effluent disposal programs will need to be ascertained.
Physio-Morphological and Compositional Variation in Ripe Fruit of Three Mango Varieties
Hossain, M. M.,M.A. Haque,M. A. Rahim,M. H. Rahman
Journal of Biological Sciences , 2001,
Abstract: Three varieties of mango were selected to find out the physio-morphological and chemical compositional differences in the fruits. Amrapali possessed highest pulp with skin (87.12%) and lowest stone (11.88%) but the fresh fruit weight was minimum (221.33 g). The variety of Bishawanath had the highest fresh weight (256.0 g) and stone (18.67%) and lowest in pulp with skin (81.33%), pulp stone ratio (4.4:1) and keeping quality (8.75 days). Keeping quality was maximum in Amrapali (12.5 days). Total sugar (26.85%), TSS (23.50%) and pH of pulp (6.0) were maximum in Amrapali, but Bishawanath showed maximum titratable acidity (0.87%) and Vitamin C (14.20 mg/100 g).So, Amrapali was superior in respect of all characters to other varieties.
Public Perception of Physical Risks: Effect of the Experience of Repeated Explosion Accidents at a Chemical Plant  [PDF]
Yusuke Koshiba, Hideo Ohtani
Open Journal of Safety Science and Technology (OJSST) , 2015, DOI: 10.4236/ojsst.2015.52006
Abstract: To explore the influence of experiencing accidental explosions, a questionnaire-based survey was conducted. This paper compares the risk perception characteristics of inhabitants living near a chemical plant at which accidental explosions occurred (group A) and of those living near a plant where no serious accidents have occurred (group B). The survey forms contain the following items: demographics, knowledge about causes of accidental explosion, dread, frequency, and risk rating variables. In addition, participants of group A are asked about their level of participation in physical risk communication. The survey reveals that 1) participants of group A have a greater sense of dread than those of group B; 2) participants of group A are more likely to perceive accidental explosions in chemical plants that occur more frequently; 3) risk rating of physical risks is independent of that of health risks; 4) the “frequency” variable is a key factor that influences decision making whether they participate in physical risk communication or not.
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