东海全新世沉积强度分区

主要按年代地层学 1 0 .3ka B.P.～ 1 2 ka B.P.,参考岩性和生物地层学方法 ,统一和确认了东海全新统底界。综合分析东海 52个钻孔和柱状岩芯资料 ,进行了全新世沉积强度分区 ,按沉积速率高低分为现代长江水下三角洲沉积区、浙闽近岸浅海沉积区、陆架东北冷涡沉积区、陆坡与冲绳海槽沉积区以及陆架残留沉积区。并对各区的沉积机理作了分析解释。

IgA肾病患者系膜区补体C3沉积强度与病情程度的关系

目的探究IgA肾病患者系膜区补体C3沉积强度与病情程度的关系。方法选取323例经皮肾活检穿刺术确诊的IgA肾病患者为研究对象,根据肾小球系膜区是否存在C3沉积、C3沉积强度分为C3阴性组、C3阳性组、C3强阳性组,比较三组血肌酐(Scr)、肾小球滤过率(eGFR)、血清C3、血清IgA、24 h尿蛋白定量水平及Lee病理分级差异。结果323例IgA肾病患者中,C3阴性组、C3阳性组、C3强阳性组分别为29、246、48例。三组血清IgA、24 h尿蛋白定量水平比较均无显著差异(P>0.05);Scr比较,C3阳性组、C3强阳性组均高于C3阴性组(P<0.01),C3强阳性组高于C3阳性组(P<0.01);eGFR比较,C3阳性组、C3强阳性组均低于C3阴性组(P<0.01),C3阳性组、C3强阳性组比较无显著差异(P>0.05);血C3比较,C3阳性组、C3强阳性组均低于C3阴性组(P<0.01),且C3强阳性组低于C3阳性组(P<0.05);C3阴性组、C3阳性组、C3强阳性组三组间Lee病理分级比较有显著差异(P<0.01)。结论IgA肾病患者系膜区补体C3沉积强度越强,肾脏病理损伤越严重,患者病情越重。

煤尘沉积强度和粒度分布的研究

为了掌握采掘巷道煤尘的沉降规律，进一步完善采掘工作面的防尘措施，对采掘巷道的煤尘沉积强度和粒度分布进行了测定，归纳了落尘分布的特点。并根据所归纳的特点完善了采掘工作面的防尘措施。

垢对蜡沉积物强度及聚乙烯管道清管特性的影响

油井采出原油中含有泥沙、垢等颗粒物,在管输过程中颗粒物与原油中的蜡分子协同沉积,导致管道输量降低,严重时可能造成管道堵塞,影响原油管道安全输送。对掺垢蜡沉积物进行了屈服应力测试实验和显微特性实验;对室内聚乙烯管道进行了清管实验;基于清管实验结果,利用π定理建立了清管效率预测模型。结果表明,碳酸钙垢对蜡沉积物强度的影响存在临界垢质量分数;沉积物中含垢,会提高清管器的蜡层破坏力和清管效率;通过室内实验和第三方文献实验数据,验证了所建立的模型。

基于蛟龙号载人潜水器的深海非接触磁力驱动式沉积物贯入强度测量装置设计

沉积物贯入强度探测是一种重要的深海沉积物强度原位测试技术。针对7000米级深海极端环境特点及精细化原位测量科学需求,开展了一种基于蛟龙号载人潜水器的深海非接触强磁式沉积物贯入强度原位测量装置研究,突破了原有贯入强度测量技术在7000米级深海结构复杂,无法实现原位、精细化测量的问题,提出了一种基于载人潜水器的永磁体力平衡传导非接触原理解决深海耐压与应变片形变传导的技术方法,并完成了样机研制及深海海上试验,取得了良好的测试效果。整套系统采用自容式工作方式进行数据的采集及存储,可与计算机连接实现数据原位读取,作业水深7000 m,贯入深度最大250 mm,测量量程0~100 kPa,精度可达5%~10%FS。2021年3月在帕里希维拉海盆,搭载蛟龙号载人潜水器在181、185潜次中完成了5200 m及6650 m海试应用,成功获得土工力学数据。

矿井煤尘沉积强度的测定分析及防治对策

采用"吊盘法"测定了煤矿风巷、瓦斯巷、采区回风巷、运掘进巷的平均沉降速度、煤尘沉积强度等参数。用直方图、回归分析法等方法对测定和计算结果进行了具体的分析,根据分析结果提出了防尘建议。研究发现漳村煤矿的风巷、瓦斯巷煤尘沉积强度较低,运掘进巷煤尘沉积强度较高但离工作面越远越低,建议在现有防尘措施的基础上采用撒布岩粉、引进ZYB-S型自动产气式抑爆装置等方式抑制落尘变扬尘。

南海北部陆坡表层沉积物强度特征研究

随着海洋开发活动由浅海走向深海，南海北部陆坡的沉积物强度特性逐渐成为关注热点。本文通过参与2015年与2016年共享航次计划，在南海北部莺琼陆坡、神狐陆坡、东沙陆坡、台湾浅滩陆坡进行沉积物重力取样与箱式取样，并现场剖样，用以进行沉积物强度测试。地质取样结果表明东沙陆坡砂含量相对较高并发现直径约22cm黑色气孔状碳酸盐结核。在神狐陆坡沉积物表层发现活体壳类生物，在110cm深度处发现壳类生物遗骸。十字板剪切试验与笔式贯入试验结果表明南海北部陆坡，沉积物强度差异较大。但总体而言，除东沙陆坡外，莺琼陆坡、神狐陆坡、台湾浅滩陆坡表层沉积物强度一般较低。0～20cm范围内，笔式贯入阻力一般小于0.1N，十字板剪切强度最大一般不超过10kPa。0～300cm深度范围内，沉积物强度沿深度方向大致呈递增趋势，个别站位递增趋势不明显。台湾浅滩陆坡等南海北部陆坡表层沉积物存在强度分层：分层界面以上，沉积物强度较低；分层界面处，沉积物强度骤增。该分层界面可能是海底滑坡的潜在滑动面。

砂质沉积物强度动力贯入室内试验研究

自由下落式CPT测试技术(FF-CPT)是新兴的海上沉积物强度测试方法。本文构建了海上FF-CPT原型样机,并以海洋干砂质沉积物为研究对象,分析了FF-CPT的贯入特征、速度相关性及其影响因素。结果表明,装置触底速度与最终贯入沉积物的深度受装置释放高度影响,释放高度越大,则触底速度与贯入沉积物深度越大。贯入过程的阻力分布规律是影响速度变化的主要因素。FF-CPT初始贯入阶段,沉积物贯入阻力随深度线性增加,但增幅不明显,这导致贯入速度变化不大,几乎可视作匀速,该段行程超过总贯入深度的2/3。后段行程贯入阻力骤增,导致贯入速度迅速降低至0。对于干砂质沉积物,FF-CPT贯入阻力与贯入速度不存在正相关关系。FF-CPT贯入阻力的速度相关性与装置质量、沉积物密实度关系不大。

天然气水合物体系动态演化研究(Ⅱ):海底滑坡

天然气水合物被认为是大陆边缘沉积物强度变弱的一个因子,从而能解释大陆边缘海底滑坡的一些观测现象.天然气水合物的形成使沉积物强度增加,而其分解则使沉积物强度变弱.虽然无法直接观测沉积物中天然气水合物的活动过程与相应的海底滑坡,大量的背景资料表明,天然气水合物崩解常常有助于触发海底沉积物块体的运动.此外,大型滑塌可以释放大量的固态天然气水合物,水合物在水柱中上浮.大块天然气水合物可以在分解前到达海洋的上部层,一些甲烷可以直接进入大气中.本文综述与天然气水合物体系演化有关的海底滑坡的研究现状.

非金属复合管防蜡性能研究

非金属管道具有耐腐蚀性强、延缓结蜡、隔热效果好等优点。本文以石蜡和白油配制模拟油,对比考察了非金属复合连续管与常规金属管的蜡沉积量和蜡沉积强度,结果表明,非金属复合连续管的结蜡量要低于常规金属管,非金属复合连续管在不同含蜡量(16.7%、20%、25%、30%、35%)情况下沉积蜡层抗剪阻力均低于常规金属管,前者的蜡沉积物更容易剥离。

非金属连续复合管防垢性能研究

非金属材料管道具有耐腐蚀、延缓结蜡、隔热效果好等优点,常用于油田集输、注水等生产过程。为了探讨非金属管与金属管的防垢性能差异,根据行业标准SY/T 5673—2020《油田用防垢剂通用技术条件》配制了结垢液,考察了非金属复合连续管与常规金属管的垢沉积量和垢沉积强度。垢沉积量实验表明,在温度60、70、80、85、90℃,结垢时间1~10 d,非金属复合连续管的结垢量要低于常规金属管,占金属管结垢量的44.4%~69.8%;垢沉积强度实验表明,非金属复合连续管临界载荷L;、L;、L;均低于常规金属管,L;、L;、L;分别占金属管的25.8%~41.4%、26.5%~94.2%、51.6%~60.1%,在较小的载荷下,划入深度较深的非金属复合连续管的垢表面相对更容易被破坏。

Effect of initial deposition behavior on properties of electroless Ni-P coating on ZK60 and ME20 magnesium alloys

The composition of magnesium alloys is greatly associated with initial deposition behavior of electroless Ni-P coatings.Thus,the initial deposition behavior of electroless Ni–P coatings on ZK60 and ME20 alloys was investigated.The results indicated that differences in the alloy compositions significantly influenced the initial deposition process and the adhesive strength,corrosion resistance,and crystal structure.The initial deposition of coatings on ZK60 and ME20 alloys preferentially occurred on the precipitates.The precipitates in ZK60 alloy had higher chemical activity after HF activation and controlled the initial deposition rate of the coating.The initial deposition rate of the coating on ME20 alloy mainly depended on the density of the Mg F2 film formed by HF activation rather than on the precipitates.Owing to differences in the initial deposition process,the coating on ZK60 alloy had higher adhesive strength and better corrosion resistance than that on ME20 alloy.The coatings on ZK60 and ME20 alloys mainly had crystalline structures,and the coating on ME20 alloy had also a slight microcrystalline structure.

In situ TiB2/Cu composites fabricated by spray deposition using solid-liquid and liquid-liquid reactions

In situ TiB2/Cu composites were fabricated by both solid-liquid(S-L)and liquid-liquid(L-L)reactive spray deposition in combination with cold rolling and annealing.The microstructure and properties of the fabricated TiB2/Cu composites were investigated.The results show that the reactive mode and rolling treatment are the main factors affecting the microstructure and properties of the TiB2/Cu composite.The in situ reaction in the L-L reaction can be carried out more completely.By controlling the rolling and annealing process,the relative density and the properties of the as-deposited composites are optimized.The comprehensive performance of the deformed TiB2/Cu composite prepared by L-L reactive spray deposition(401 MPa and 83.5%IACS)is better than that by S-L reactive spray deposition(520 MPa and 20.2%IACS).

Grain Size Distribution of Soils within the Cordillera Blanca, Peru: An Indicator of Basic Mechanical Properties for Slope Stability Evaluation

This paper presents results of a study on the mechanical properties of sandy and gravely soils within the Cordillera Blanca, Peru. The soils were divided into groups according to their origin(glacial, fluvial, or debris flow). The grain size distribution of forty three soil samples was used to classify the soils according to the scheme of the Unified Soil Classification System(USCS). These distributions have then been used to estimate shear strength and hydraulic properties of the soils. There are clear differences between the soils which reflect their divergent origins. The glacial soils normally fit within one of two distinctive groups according to the proportion of fines(Group A, 7%-21.5%; Group B, 21%-65%). The estimation of shear strength at constant volume friction angle and peak shear strength of the glacial sediments with low content of fines was made using published data relating to the measured shear strength characteristics of soils with similar origins and grain size distributions. The estimated values were supported by measurements of the angle of repose taken from fourteen samples from two moraines and by shear tests on samples from one locality. The results of the grain size distribution werealso used to estimate the average hydraulic conductivity using the empirical Hazen formula which results were verified by field infiltration tests at two localities.

Release of Mercury from Intertidal Sediment to Atmosphere in Summer and Winter

The release of mercury from intertidal sediment to atmosphere was studied based on the simulated experiment. The experiment samples were collected from the Haibo Estuary (S1) and the Licun Estuary (S2) of the Jiaozhou Bay in China,which are seriously polluted with mercury. The results show that the mercury in sediment releases rapidly to atmosphere under solar radiation. After 8 hours of solar radiation,mercury concentrations decrease from 5.62 μg/g and 2.92 μg/g to 2.34 μg/g and 1.39 μg/g in S1 and S2 sediments respectively in summer,and decrease from 5.62 μg/g and 2.92 μg/g to 4.58 μg/g and 2.13 μg/g respectively in winter. The mercury species in the sediment change markedly under solar radiation. The concentrations of mercury bound to organic matter decrease significantly from 2.73 μg/g to 0.31 μg/g in S1 and from 2.07 μg/g to 0.31 μg/g in S2,and the released mercury mainly comes from mercury bound to organic matter. Mercury flux shows distinguishing characteristic of diurnal change,and it increases rapidly in the morning with the rising of solar radiation intensity,but decreases in the afternoon. The mercury flux increases with sediment temperature and solar radiation intensity. The rapid release of mercury in intertidal sediment plays an important role in the regional mercury cycle.

Shear creep parameters of simulative soil for deep-sea sediment

Based on mineral component and in-situ vane shear strength of deep-sea sediment, four kinds of simulative soils were prepared by mixing different bentonites with water in order to find the best simulative soil for the deep-sea sediment collected from the Pacific C-C area. Shear creep characteristics of the simulative soil were studied by shear creep test and shear creep parameters were determined by Burgers creep model. Research results show that the shear creep curves of the simulative soil can be divided into transient creep, unstable creep and stable creep, where the unstable creep stage is very short due to its high water content. The shear creep parameters increase with compressive stress and change slightly or fluctuate to approach a constant value with shear stress, and thus average creep parameters under the same compressive stress are used as the creep parameters of the simulative soil. Traction of the deep-sea mining machine walking at a constant velocity can be calculated by the shear creep constitutive equation of the deep-sea simulative soil, which provides a theoretical basis for safe operation and optimal design of the deep-sea mining machine.

Effect of electropulsing on anisotropy in strength of laser metal deposited Ti-6Al-4V alloy

The effect of electropulsing treatment on microstructure and mechanical strength of laser metal deposited Ti−6Al−4V alloy was investigated in order to eliminate the anisotropy in strength of laser metal deposited Ti−6Al−4V alloy by tensile tests,optical microscopy,scanning electron microscopy,electron back-scattered diffraction analyses and transmission electron microscopy.With increasing applied voltages from 0 to 130 V,the evolution of microstructure within columnarβgrains followed the sequence ofα′martensite→colonyαstructure→basket-weaveαstructure.The electropulsing treated at 130 V weakened the texture of martensite withinβgrains.The as-built Ti−6Al−4V alloy showed an anisotropy in yield strength(6.2%).After processing at 130 V,the anisotropy in yield strength was reduced to 0.6%,which was attributed to the almost equivalent distribution of Schmid factor in the samples deformed along different orientations.

Large-area Analysis of Soil Erosion and Landslides Induced by Rainfall: A Case of Unsaturated Shallow Deposits

Unsaturated shallow soil deposits may be affected by either superficial soil erosion or shallow landslides in adjacent or overlapping source areas and in different seasons when a different soil suction exists.The triggering analysis of both these processes is a relevant issue for the hazard analysis while the literature mostly provides specific approaches for erosion or for landslides.The paper proposes a largearea analysis for a case study of Southern Italy,consisting of unsaturated shallow deposits of loose pyroclastic(air-fall) volcanic soils that have been repeatedly affected by erosion and landslides in special seasons.For a past catastrophic event, the simulated source areas of shallow landslides are smaller than those observed in the field while the simulated eroded areas with thickness greater than 5cm are comparable with the in-situ evidences, if the analysis takes into account high rainfall intensity and a spatially variable soil cover use.More in general, the results of the paper are consistent with the previous literature and also provide a methodological contribution about the application of distinct tools over large area.The added value is that the paper shows how the combination of distinct large-area analyses may help with understanding the dominant slope instability mechanisms.Only once this goal is fully achieved, can specific physically-based analyses be confidently performed at detailed scales and for smaller specific areas.

Dated deposition couplets link catchment erosion flux with storm discharge on the Chinese Loess Plateau

Tracing erosion flux within a single catchment is one of the major targets for the Earth's Critical Zone science. The sedimentary succession in landslide-dammed reservoirs within the Chinese Loess Plateau(CLP) serves as a valuable archive of past erosion history. Deposition couplets and annual freeze–thaw layers were firstly identified for the sedimentary succession of the Jingbian reservoir on the northern CLP with high-resolution XRF core scanning. The deposition couplets in the reservoir since 1963 A.D. were further dated with ^(137) Cs activity. We found consistent one-to-one correspondence between couplet specific sediment yield and storm intensity. The reconstructed soil erosion history highlights the control of storm intensity and frequency on loess erosion on the northern CLP in the past hundreds of years.