浅谈灰土挤密桩与DDC桩在工程实践中应用与发展

DDC桩是挤密桩的一种新型桩。根据宝鸡某大型电厂中DDC桩与灰土挤密桩地基处理工程实例,从挤密机理、挤密效果、复合地基承载力与抗变形性状及复合地基浸水稳定性等诸方面进行了系统地分析对比,进而探讨挤密桩地基的应用与发展。     

关于垃圾填埋场渗滤系统渗透性能经时变化的研究

利用模拟实验对垃圾填埋场中渗滤系统的渗透性能与填埋时间的关系进行了研究。采用焚烧灰、土工织物和碎石导流层组成渗透系统,研究了实验时间对渗滤系统的渗透系数以及结晶物颗粒直径的影响。结果表明:由于垃圾焚烧灰中硅酸钙和铝酸钙的结晶作用,随着渗透时间的增加,吸附在土工织物表面的物质逐渐增多,使颗粒之间更紧密,导致空隙减小影响渗滤系统的渗透性能。根据研究结果,在垃圾焚烧灰填埋时,垃圾焚烧灰压实密度不要太高,这样有利于渗滤液的排放。     

Temporal and spatial dynamical simulation of groundwater characteristics in Minqin Oasis

Application scope of geostatistics has been gradually extended from original geologic field to soil science and ecological field, etc. and its successful application results have been widely demonstrated. But little information is reported as to the direct use of geostatistical method to work out the distribu- tion map of groundwater characteristics. In this paper the semivariogram of geostatistics, in combina- tion with GIS, was used to quantitatively study the spatial variation characteristics of groundwater table depth and mineralization degree and their relation to the landuse changes. F test of the used spherical model reached a very significant level, and the theoretical model can well reflect the spatial structural characteristics of groundwater table depth and mineralization degree and achieve an ideal result. This shows that the application of the method in the dynamical simulation of groundwater is feasible. And this paper also provides useful reference for the application of geostatistics in the study of the dy- namical variations of groundwater resources in the oasis.     

RG-1测汞仪软件介绍

RG1测汞仪操作软件使用VC++5.0工具研制,在Windows95下运行。通过AD/DA接口实现对RG1的控制和对基准电压的自动跟踪校正。完全的可视化操作。具有4种可选的标准曲线拟合方法以用于不同浓度样品的峰值和积分值测量,并直接给出汞浓度及各种统计数据     

Massive sedimentation of fine sediment with organic matter and enhanced benthic-pelagic coupling by an artificial dyke in semi-enclosed Chonsu Bay, Korea

To assess the impact of an artificial dyke in Chonsu Bay (CBD) on the organic carbon (C(org)) cycle, we measured excess (210)Pb activities, C(org) and nitrogen content in sediment cores. The C(org) oxidation rates (C(ox)) on the surface sediment and benthic nutrient fluxes were also quantified with an in situ benthic chamber. The higher excess (210)Pb inventory, C(org) and nitrogen in cores near the CBD indicated lateral transport and local, massive deposition of particulate matter due to tidal circulation altered by artificial dyke construction. The C(ox) in sediment near the CBD was about twice as high as that out of the bay, suggesting the importance of benthic remineralization of organic matter. The benthic fluxes of dissolved inorganic nitrogen and phosphate were four to six times higher than those outside the bay, corresponding to 141% and 131% respectively, of the requirements for primary production.     

河北唐山地区中寒武统张夏组鲕粒灰岩的岩石学研究

本区张夏组鲕粒灰岩内,广泛见到细径放射鲕和较粗的同心-放射鲕.放射鲕中存在连生体,我们称之“连生鲕”.与赵震等(1984)人工合成的静水鲕对比,区内放射鲕亦系静水条件下生成;因未见长串连生体,仅呈现数鲕(2—4个)连生,表明鲕粒生成后遭到搅动水拆开.由此可以认为,本组鲕粒灰岩属间歇高能成因模式的产物。又按该类岩石显示的成岩特征,可知本区鲕粒灰岩经历过多种成岩环境,至今仍保留较为明显的大气成岩环境的标志.     

凤城市赛马镇风洞洞穴特征及发育基本条件

赛马镇风洞是我国东北规模较大的岩溶洞穴,洞长在2000m以上,已探测长度1265m.风洞具有纵坡降较小、支洞繁多、形态奇异及国内罕见的溶蚀景观“天锅”等特征.岩性、构造、水文地质特征等是控制洞穴发育的基本条件.风洞的发育约始于中更新世40万年前.     

琼东南盆地华光凹陷天然气水合物稳定带厚度的影响因素

为了探讨琼东南盆地华光凹陷海底天然气水合物稳定带的分布规律,定量研究了静水压力、底水温度、地温梯度和气源组分对水合物稳定带的影响程度。在此基础上,分析了华光凹陷现今甲烷水合物稳定带的厚度分布。最后,综合各因素的历史演化过程,初步探讨了华光凹陷1.05 Ma BP以来天然气水合物稳定带的演化。结果表明:(1)气源组分和海底温度的变化对研究区内水合物稳定带的影响较大;水合物稳定带厚度与海底温度呈良好的线性负相关性。(2)水深超过600 m的海域具备形成天然气水合物的温压条件;超过600 m水深的海域水合物稳定带厚度大部分超过 100 m,其中西北部稳定带的最大厚度超过300 m,是有利的水合物勘探区。(3)华光凹陷1.05 Ma BP以来天然气水合物稳定带厚度经历了快速增厚–窄幅变化–快速减薄和恢复的过程。麻坑群与水合物稳定变化敏感区在空间上具有较好的叠合关系。结合前人的研究成果,推测其形成与天然气水合物的分解释放有关。     

Single Nucleotide Polymorphism of FSHβ Gene Associated with Reproductive Traits in Japanese Flounder (Paralichthys olivaceus)

Follicle stimulating hormone β (FSHβ) of Japanese flounder (Paralichthys olivaceus) plays a key role in the regulation of gonadal development.This study aimed to investigate molecular genetic characteristics of the FSHβ gene and elucidate the effects of single nucleotide polymorphisms (SNPs) of FSHβ on reproductive traits in Japanese flounder.We used polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and sequencing of the FSHβ gene in 60 individuals.We identified only an SNP (T/C) in the coding region of exon3 of FSHβ.The SNP (T/C) did not lead to amino acid changes at the position 340 bp of FSHβ gene.Statistical analysis showed that the SNP was significantly associated with testosterone (T) level and gonadosomatic index (GSI) (P0.05).Individuals with genotype TC of the SNP had significantly higher serum T levels and GSI (P0.05) than that of genotype CC.Therefore, FSHβ gene could be a useful molecular marker in selection for prominent reproductive trait in Japanese Flounder.