基于DOW分析法的某石化库安全评价

某石化库储存品种具有闪点低、毒性高、爆炸范围宽的特点。为了对其进行全面、科学的安全评价,运用DOW分析法对某石化库进行安全分析,得出评价单元5的MPPD(实际)最高,为重点监管区域。结果表明,该方法计算简单,评价结果真实可靠,能够对石化库进行切实可行的安全评价。

土石坝心墙沥青混凝土原材料选用问题的探讨

针对工程实践中对于南疆库石化沥青与骨料粘附性能及天然砾石骨料对心墙沥青混凝土长期水稳定性能的影响等问题的担忧,结合新疆某在建碾压式沥青混凝土心墙坝工程,采用南疆库石化70号(A)级道路石油沥青与天然砾石骨料分别配制心墙沥青混凝土,进行相关物理力学性能试验。结果表明,库石化沥青技术性能可满足现行规范要求,粘附性较北疆克石化70号(A)级道路石油沥青略低,长期水稳定性能相差不大;天然砾石骨料与沥青粘附性稍差,使用水泥作填料可有效改善骨料与沥青的粘附性,提升心墙沥青混凝土的水稳定性能。研究成果拓宽了沥青心墙原材料的选用范围,推动了新疆沥青“北克南库”的应用格局。

Optimum blending of iron ore from Choghart stockpiles by using goal programming

Iron and steel industry is an important sector of Iran's economy.Choghart iron ore mine is an important iron ore producer of Iran steel industry.Phosphorous contained in the iron ore concentrates of Choghart mine has a detrimental effect on the steel making process,whereby this causes cracks to form in the refractory lining of blast furnaces.In the past,about 1.43 Mt of low-grade and 4.53 Mt of high-phosphorous materials had been transported to low grade and high phosphorous stockpiles,respectively,for future beneficiation.As a result of the progressive depletion of high-grade ore and establishment of beneficiation plant in Choghart,exploitation of these two stockpiles in this mine became an important issue.In this work,a linear goal programming(GP) model was developed in order to determine the optimum iron ore blend in terms of quality from low grade and high phosphorous stockpiles of Choghart mine.The model was solved by the SOLVER V.9 program.Results show that feeding with acceptable quality(w(Fe)≥50% and w(P)≤1.2%,mass fraction) materials can be blended from stockpiles that satisfy the needs of the Choghart processing line.

Application Research of Oil Development Costs in Reservoir Management

Based on oil development costs, the application research in the technical and economic limits calculation of oil development and the production optimal allocation to all the oilfields, was finished. At the same time, according to the regression of real development costs, a new method for oil well economic water cut and oil well economic rate are set up, the production optimal allocation is developed with satisfactory results.

A new genus of galeaspids(jawless stem-Gnathostomata)from the early Silurian Chongqing Lagerstätte,China

The early Silurian Chongqing Lagerstätte(middle Telychian)yields exceptionally preserved articulated jawless and jawed fishes.Here,we describe a new eugaleaspiform(Galeaspida,jawless stem-Gnathostomata),Miaojiaaspis dichotomus gen.et sp.nov.,from the Chongqing Lagerstätte in Xiushan,Chongqing,China.The new form resembles Tujiaaspis vividus in the short medial dorsal canal,and the presence of the branching ends of the lateral transverse canal.They differ in that T.vividus has highly developed subordinate branches of the sensory canals that form a reticulate sensory canal system,and the median dorsal opening is more elongated.Our phylogenetic analysis recovers M.dichotomus and T.vividus as a monophyletic clade(Tujiaaspidae fam.nov.),which is supported by two synapomorphies:the short medial dorsal canal,and the branching ends of the lateral transverse canal.Tujiaaspidae forms a trichotomy with Shuyuidae and a clade comprising Anjiaspis,Sinogaleaspidae,Yongdongaspidae,and the‘eugaleaspid cluster’.The sensory canal patterns in galeaspids are compared to show the transformation sequence of the sensory canal system in Eugaleaspiformes.

Exceptionally preserved brachiopods from the Chengjiang Lagerst(a|¨)tte(Yunnan,China):Perspectives on the Cambrian explosion of metazoans

The Cambrian explosion was coined to describe the geologically sudden appearance of numerous bilaterian body plans(Phyla)around the Ediacaran-Cambrian transition,around 565-520million years ago.Many explanations and conjectures have been postulated in order to explain the pattern and duration of this explosive radiation of many different phyla of early metazoans.Here,we focus on the evolution of a phylum of marine suspension-feeding animals—the brachiopods,as exemplified by the exceptionally preserved taxa from the celebrated Chengjiang Konservat Lagerst(a|¨)tte(Yunnan,China).The abundant soft-bodied preservation at these fossil quarries gives us the only firm insights into what brachiopods looked like and how they functioned and lived when they first appeared on the Earth.Studies of Chengjiang brachiopods demonstrate that the early animals developed a remarkably varied organization of tissues and organs shortly after the onset of Cambrian explosion.In the marine suspension-feeding brachiopods,most importantly the tentaculate feeding structure of early brachiopods is already differentiated into two shapes of lophophore,anteriorly coiled(spiralled)and posteriorly arching tentacle crowns and the unique latter type was previously not documented from fossil and living brachiopods.Also unlike any known Recent brachiopod,all the known Cambrian brachiopods from Chengjiang have an open digestive tract that was disposed either as a Ushaped gut in linguliform and stem group brachiopods,or straight gut with a posterior anus in some calcareous-shelled stocks.Moreover,in contrast toliving lingulids,all the Cambrian brachiopods have an epibenthic lifestyle either cemented by a ventral valve or attached by variable pedicles to establish complex ecological community encompassing primary tierers and variable secondary tierers.It is therefore assumed that brachiopods were the first benthic metazoan that achieved their success in ecological stratification and tiering complexity by late Atdabanian.The setae are also important for the brachiopod suspension-feeding life style,and in the Chengjiang braehiopods they include two types cilia-like and spine-like setae.The mantle canals of different braehiopod species are also distinctly variable in arrangement,mainly disposed in pinnate,baeulate and peripheral conditions.Of these,the peripheral disposition of mantle canals is for the first time proposed here so as to differentiate from the bifurcate condition in recent lingulids in that the former is devoid of posteriorly extending main trunks of sinus,but possesses a diverging dorsal vascula media in dichotomy.

First report of brachiopods with soft parts from the Lower Cambrian Latham Shale (Series 2, Stage 4), California

Exceptionally preserved faunas have greatly improved our understanding of animal origin and evolution,and systematic investigations of Cambrian sediments around the world during the last two decades have led to a dramatic increase in the num-bers of Konservat-Lagerstatten[1].

Water-Extractable Carbon Pools and Microbial Biomass Carbon in Sodic Water-Irrigated Soils Amended with Gypsum and Organic Manures

Microbial biomass carbon (MBC), a small fraction of soil organic matter, has a rapid turnover rate and is a reservoir of labile nutrients. The water-extractable carbon pools provide a fairly good estimate of labile C present in soil and can be easily quantified. Changes in soil MBC and water-extractable organic carbon pools were studied in a 14-year long-term experiment in plots of rice-wheat rotation irrigated with canal water (CW), sodic water (SW, 10-12.5 mmol c L-1 residual sodium carbonate), and SW amended with gypsum with or without application of organic amendments including farmyard manure (FYM), green manure (GM), and wheat straw (WS). Irrigation with SW increased soil exchangeable sodium percentage by more than 13 times compared to irrigation with CW. Sodic water irrigation significantly decreased hot water-extractable organic carbon (HWOC) from 330 to 286 mg kg-1 soil and cold water-extractable organic carbon (CWOC) from 53 to 22 mg kg-1 soil in the top 0-7.5 cm soil layer. In the lower soil layer (7.5-15 cm), reduction in HWOC was not significant. Application of gypsum alone resulted in a decrease in HWOC in the SW plots, whereas an increase was recorded in the SW plots with application of both gypsum and organic amendments in both the soil layers. Nevertheless, application of gypsum and organic amendments increased the mean CWOC as compared with application of gypsum alone. CWOC was significantly correlated with MBC but did not truly reflect the changes in MBC in the treatments with gypsum and organic amendments applied. For the treatments without organic amendments, HWOC was negatively correlated with MBC (r = 0.57*) in the 0-7.5 cm soil layer, whereas for the treatments with organic amendments, both were positively correlated. Irrigation with SW significantly reduced the rice yield by 3 t ha-1 and the yield of rice and wheat by 5 t ha-1 as compared to irrigation with canal water. Application of amendments significantly increased rice and wheat yields. Both the rice yield and the yield of rice and wheat were significantly correlated with MBC (r = 0.49**-0.56**, n = 60). HWOC did not exhibit any relation with the crop yields under the treatments without organic amendments; however, CWOC showed a positive but weak correlation with the crop yields. Therefore, we found that under sodic water irrigation, HWOC or CWOC in the soils was not related to MBC.

Plant Cover and Soil Biochemical Properties in a Mine Tailing Pond Five Years After Application of Marble Wastes and Organic Amendments

Tailing ponds pose environmental hazards, such as toxic metals which can contaminate the surroundings through wind and water erosions and leaching. Various chemical and biochemical properties, together with extractable and soluble metals were measured five years after reclamation of a polluted soil affected by former mining activities. This abandoned mine site contains large amounts of Fe-oxyhydroxides, sulphates, and heavy metals. As a consequence, soils remain bare and the soil organic matter content is low （〈 3 g kg-1）. Marble waste, pig manure and sewage sludge were applied in 2004. Plant cover and richness, and soil chemical, biochemical and biological parameters were analysed five years later. Results showed that all soil biochemical properties as well as vegetation cover and richness were higher in treated soils than in the untreated contaminated plots （control）, although organic matter, pH values and extractable metals concentrations were similar among treatments. Soluble cadmium and zinc were lower in the amended plots than in control.