一次性免堆载预压技术研究与应用          下载免费PDF全文

冯士广  纪燕祥  尹春播  丁宁宁  赵志杰  孙宇佳  何若梅  戚霁  侯永革  邸凯强 《探矿工程》2019,46(5):72-77

软土地基处理恰当与否,关系到整个工程质量、投资和进度,其重要性已越来越多地被人们所认识。通过开展一次性免堆载预压技术研究,根据排水固结原理及桩体自身抗拔力,用三维固结筒实现饱和软土无外来荷载条件下的一次性快速排水固结,提高地基土抗剪强度、降低压缩性、改善透水性及动力特征。  相似文献   

Fifteen years progress of the TRITON array in the Western Pacific and Eastern Indian Oceans     

Kentaro Ando  Yoshifumi Kuroda  Yosuke Fujii  Tatsuya Fukuda  Takuya Hasegawa  Takanori Horii  Yasuhisa Ishihara  Yuji Kashino  Yukio Masumoto  Keisuke Mizuno  Motoki Nagura  Iwao Ueki 《Journal of Oceanography》2017,73(4):403-426

The Triangle Trans‐Ocean Buoy Network (TRITON) project by the Japan Agency for Marine-Earth Science and Technology began with deployment in the western tropical Pacific Ocean in 1998 and has shifted to steady, long-term observations since 1999. After on-site inter-comparison with the Autonomous Temperature Line Acquisition System mooring system of the Tropical Atmosphere and Ocean (TAO) array by the National Oceanic and Atmospheric Administration, the TRITON array became the international TAO/TRITON array in 2000 as a key component of the Global Ocean and Climate Observing Systems. The TAO/TRITON array took over from the TAO array, which was developed during the Tropical Ocean and Global Atmosphere program (1985–1994), and replaced the western part of TAO with new additional real-time measurements of salinity and ocean currents. In 2001, two TRITON moorings were deployed in the eastern Indian Ocean for capturing the eastern pole of the Indian Ocean Dipole. From this initiative, the Indian Ocean Observing System (IndOOS) was designed, and the Indian Ocean mooring array (Research Moored Array for Africa–Asian–Australian Monsoon Analysis and Prediction) was developed as a key component of IndOOS. In this paper, 15 years of progress in the TRITON project in the western Pacific and eastern Indian Oceans is reviewed with regards to scientific outcomes, technological development, and collaborations with international and domestic partners. Future directions for sustainable observation in the Pacific and Indian Oceans are also discussed.  相似文献   

ESR/U-series chronology of the Lower Palaeolithic palaeoanthropological site of Visogliano, Trieste, Italy     

Christophe Falgures  Jean-Jacques Bahain  Carlo Tozzi  Giovanni Boschian  Jean-Michel Dolo  Norbert Mercier  Hlne Valladas  Yuji Yokoyama 《Quaternary Geochronology》2008,3(4):390-398

The Visogliano shelter, in north-eastern Italy, is an important Middle Pleistocene occupation site where human remains were found together with an archaic lithic industry, including choppers, chopping tools and a few protobifaces. It is of utmost importance to try to document this period, when a second wave of settlement colonised Western Europe, carrying new flaking techniques and tools.Combined ESR/U-series analyses, integrated with biostratigraphical and environmental data, define a chronological frame for the layers from which the artefacts were unearthed. The lower levels, including human remains, can be dated to the 350–500 kyr time span, in agreement with micromammal and stratigraphical studies.These data make Visogliano one of the oldest palaeoanthropological sites in Italy, where human remains are directly associated with protobifaces, choppers and chopping tools. In Western Europe, Visogliano is contemporaneous to the G soil of the Arago Cave, France, with which it shares several similarities in faunal assemblages and radiometric data, and which contains human remains also. These data make Visogliano as one of the oldest sites in Europe where the Acheulian culture is observed.  相似文献   

Petrology of a mantle-derived rhyolite, Hokkaido, Japan     

Tetsuichi Takagi  Yuji Orihashi  Kazuki Naito  Yasushi Watanabe 《Chemical Geology》1999,160(4):368-445

The Miocene Kitami rhyolite, consisting of orthopyroxene and plagioclase-phyric lavas and dikes, occurs on the back-arc side of the Kuril arc with coeval basalts and Fe-rich andesites. Temperatures estimated from orthopyroxene–ilmenite pairs exceed 900°C. Although the whole rock compositions of the Kitami rhyolite correspond to S-type granites (i.e., high K, Al, large ion lithophile elements, and low Ca and Sr), Sr–Nd isotope compositions are remarkably primitive, and similar to those of the coeval basalts and andesites. They are distinct from those of lower crustal metamorphic rocks exposed in the area. Comparison of chondrite-normalized rare earth element (REE) patterns between the rhyolite and the basalts and andesites show that the rhyolite is more light REE enriched, but has similar heavy REE contents than the basalts. All rhyolites show negative Eu anomalies. The geochemical data suggest that did not formed by simple dehydration melting of basaltic rocks or fractional crystallization of basaltic magmas. The features of slab-derived fluids expected from recent high pressure experimental studies indicates that mantle wedge is partly metasomatized with “rhyolitic” materials from subducted slabs; it is more likely that very low degree partial melting of the metasomatized mantle wedge formed the rhyolite magma.  相似文献   

加味大黄䗪虫丸对原发性胆汁性胆管炎肝星状细胞损伤状态下TGF-β1、Smads的影响          下载免费PDF全文

熊小花  柳玉佳  杨柳 《应用海洋学学报》2023,39(8):187

目的：观察加味大黄?虫丸对原发性胆汁性胆管炎（PBC）肝星状细胞损伤状态下转化生长因子-β1（TGF-β1）、Smads的影响。方法：将20只大鼠随机分为干预组与对照组,每组各10只。干预组灌胃加味大黄?虫丸混悬液1.5 ml/100 g,对照组灌胃等量0.9%氯化钠注射液,每天1次,持续1周。将肝星状细胞T6（HSC-T6）细胞分为6组,分别为空白组、对照组、5%空白血清组、10%空白血清组、5%含药血清组、10%含药血清组,培养24 h。建立乳酸损伤模型,造模成功后分为5组：空白组、对照组、正常组、模型组、中药组。测定细胞活性,细胞中TGF-β1、Smad3、Smad7 mRNA表达,TGF-β1、磷酸化Smad3、磷酸化Smad7 mRNA蛋白表达。结果：各组HSC-T6细胞活性对照组、5%空白血清组、10%空白血清组、5%含药血清组、10%含药血清组与空白组比较,差异均有统计学意义（P<0.01）。TGF-β1、Smad3、Smad7 mRNA表达及TGF-β1、p-Smad3、p-Smad7 mRNA蛋白表达水平,模型组与空白组比较,中药组与模型组比较,差异均有统计学意义（P<0.01或P<0.05）。结论：加味大黄土?丸治疗PBC的作用机制与降低TGF-β1、Smad3水平,提高Smad7水平相关。  相似文献   

Lethality of increasing CO2 levels on deep-sea copepods in the western North Pacific     

Yuji Watanabe  Atsushi Yamaguchi  Hiroshi Ishida  Takashi Harimoto  Shinya Suzuki  Yoshio Sekido  Tsutomu Ikeda  Yoshihisa Shirayama  Masayuki Mac Takahashi  Takashi Ohsumi  Joji Ishizaka 《Journal of Oceanography》2006,62(2):185-196

The first CO₂ exposure experiments on several species of pelagic copepods inhabiting surface and deep layers in the western North Pacific were conducted. Living organisms were collected from two layers between the surface and 1,500 m between latitudes of 11 and 44°N, and they were exposed aboard ship to various pCO₂ up to about 98,000 μatm. Mortality of copepods from both shallow and deep layers in subarctic to subtropical regions increased with increasing pCO₂ and exposure time. Deep-living copepods showed higher tolerance to pCO₂ than shallow-living copepods. Furthermore, deep-living copepods from subarctic and transitional regions had higher tolerances than the subtropical copepods. The higher tolerances of the deep-living copepods from subarctic and transitional regions may be due to the adaptation to the natural pCO₂ conditions in the subarctic ocean.  相似文献   

Flow cytometric detection and enumeration of DNA and RNA viruses infecting marine eukaryotic microalgae     

Yuji Tomaru  Keizo Nagasaki 《Journal of Oceanography》2007,63(2):215-221

Sample preparation protocols for flow cytometry (FCM) analysis with five algal viruses were optimized: Heterocapsa circularisquama virus (HcV), Heterosigma akashiwo virus (HaV), Chaetoceros salsugineum nuclear inclusion virus (CsNIV), Rhizosolenia setigera RNA virus (RsRNAV) and H. circularisquama RNA virus (HcRNAV). The optimum staining protocols differed significantly among the viruses tested. FCM counts for the large DNA algal viruses HaV and HcV (∼0.2 μm in diameter) were similar to numbers determined by epifluorescence microscopy (EFM). In contrast, FCM counts of viruses smaller than 40 nm that harbor DNA (CsNIV) or RNA genomes (RsRNAV, HcRNAV) were comparable to or lower than most probable number (MPN) values, which indicate only infectious virus number, suggesting that the FCM counts were underestimates. This is presumably because their single particle fluorescence signals were below the detection limit for the flow cytometer. These results indicate that a large portion of the smaller viruses in the aquatic plankton virus community may be overlooked by FCM.  相似文献   

Latitudinal Differences in the Planktonic Biomass and Community Structure Down to the Greater Depths in the Western North Pacific     

Atsushi Yamaguchi  Yuji Watanabe  Hiroshi Ishida  Takashi Harimoto  Kazushi Furusawa  Shinya Suzuki  Joji Ishizaka  Tsutomu Ikeda  Masayuki Mac Takahashi 《Journal of Oceanography》2004,60(4):773-787

As part of the research program WEST-COSMIC Phase I (1997–2001), vertical profiles down to the greater depths (0–2000 m or 5800 m) of the plankton community structure composed of heterotrophic bacteria, phytoplankton, protozooplankton and metazooplankton were studied at one station in each subarctic (44°N) and in transitional region (39°N), and two stations in subtropical region (30°N and 25°N); all in 137–155°E in the western North Pacific Ocean. The biomass of all four taxonomic groups decreased rapidly with increasing depths at all stations, although the magnitude of depth-related decrease differed among the groups. As plankton community structure, metazooplankton biomass and bacterial biomass occupied >50% of the total in 0–2000 and 2000–4000 or 5000 m strata, respectively, at subarctic and transitional stations, while bacterial biomass contributed to >50% of the total consistently from 0 through 4800 or 5800 m at subtropical stations. Metazooplankton biomass integrated over the greater depths exhibited a clear latitudinal pattern (high north and low south), but this was not the case for those of the other taxonomic groups. As a component of metazooplankton, an appreciable contribution of diapausing copepods to the metazooplankton was noted at subarctic and transitional stations, but they were few or nil at subtropical stations. As protozooplankton assemblages, heterotrophic microflagellates (HMF) and dinoflagellates were two major components at subarctic and transitional stations, but were only HMF predominated at subtropical stations. From biomass ratios between heterotrophic bacteria, HMF and dinoflagellates, “sinking POC-DOC-heterotrophic bacteria-HMF-heterotrophic dinoflagellates” link was proposed as a microbial food chain operative in the deep layer of the western North Pacific. All results are discussed in the light of latitudinal differences in the structure and functioning of plankton community contributing to the ‘biological pump’ in the western North Pacific Ocean. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Distribution of phototrophic bacteria in Omura Bay during the summer with special reference to brownChlorobium     

Yuji Fujita  Buhei Zenitani 《Journal of Oceanography》1975,31(3):124-130

The distribution of phototrophic bacteria was investigated during the summers of 1969 and 1970 in Omura Bay of western Kyushu. Phototrophic sulfur- and nonsulfur-bacteria were distributed numerously in the mud and bottom water. Brown strains usually dominated in number. In water column, other than bottom water, there were usually few or no phototrophic bacteria. On occasion, however, a large number of brown bacteria were found in the middle of water column. Six strains, two each of the purple, green and brown bacterial colonies, were isolated from mud and sea water. The purple and green bacterial strains were identified as belonging to the generaChromatium andChlorobium, respectively. The brown strains could not be identified using Bergey's manual, but were found to be similar to the brownChlorobium described byPfennig. All six strains required sulfide for growth. Heterotrophic tendency was greater for the purple and green strains than for the brown strains. Their growth was enhanced by the addition of thymine. Living cells, taken from enrichment cultures of mud samples from four stations, gave absorption spectra almost identical to the spectrum of brownChlorobium. Thus it appears that during the summer brownChlorobium is the dominant phototrophic bacterial group in Omura Bay.  相似文献   

Surface currents around Hokkaido in the late fall of 1981 obtained from analysis of satellite images     

Yuji Hatakeyama  Sotaro Tanaka  Toshiro Sugimura  Tsukasa Nishimura 《Journal of Oceanography》1985,41(5):327-336

This paper describes the characteristics of currents around Hokkaido using a current vector map compiled by chasing the displacement of sea marks on a pair of successive thermal infrared images taken from a satellite, NOAA-6. The points of some sea surface patterns showing distinctive features which can be commonly identified in both images are called Sea Marks≓. This sea mark chase method≓ has a great advantage over velocity measurements by boats or buoys, in that it gives a synoptic view of the velocity distribution over a broad sea area extending for some hundreds of miles on a short time scale of half a day.In order to investigate the current in the late fall of 1981, we used the data taken at 19:05 JST on 30 October and at 7:20 JST on 31 October. With these data taken with a 12 hr difference, the measurement accuracy of the speed of sea marks reached ±0.1 knot through geometrical correction. The velocity vectors of sea marks agreed with results of GEK measurements performed on those days, and also with the mean current pattern obtained in the past based on sea surface data.The most distinct features recognized were some cyclonic and anticyclonic eddies of the order of 100 km in diameter which dominated in the Kuril Basin of the Okhotsk Sea. They appeared clearly in the original NOAA images and their physical parameters were determined quantitatively from the vector map. These eddies were located in the region of decay of the Soya Warm Current and were rotating at a speed nearly as large as that of the current. The problems of what feeds energy to these eddies and how long they live remain to be solved in future studies.  相似文献