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Black carbon (BC), ubiquitous in soils, plays an important role in global carbon cycles, the radiative heat balance of the Earth, pollutant fate, emissions of greenhouse gas, soil fertility, soil microbial community, and ecosystem stability. However, information on BC in topsoils of the northeastern Qinghai-Tibet Plateau is limited. Therefore, this study performed field sampling and analyzed contents of total BC and soot BC in topsoils. The results indicated that the contents of total BC in all soil samples ranged from 0.504 to 74.381 g kg−1 with an average value of 5.152 g kg−1, whereas those of soot BC were in the range of 0.400–15.200 g kg−1 with a mean value of 1.719 g kg−1. Contents of BC were significantly correlated with those of total carbon and total organic carbon. Soil types affected the distribution of soil BC. The contents of total BC in the loam soils were larger than those in the clay soils, whereas soot BC was more easily enriched in the clay soils. Total BC was negatively correlated with Ca, and soot BC was negatively correlated with Ti. The contents of soil BC in functional areas, such as agricultural and pastoral areas, industrial areas, and mining areas, were significantly higher than those in other areas, illustrating that anthropogenic activities drastically affected the distribution of soil BC. This study exhibits the fundamental information on soil BC in the northeastern Qinghai-Tibet Plateau to provide important knowledge on global soil carbon sink.

Little attention has been paid to the study of sedimentary records from DaQaidam Salt Lake regarding brine evolution and hydro-climate change. Here we report the results of AMS 14C dating and mineralogical investigation on a sediment profile D4 from the south central of perennial saline water-body. The result revealed that pinnoite deposit in the lakebed was formed in early Holocene, the lake underwent three stages of lake-level and brine evolution in Holocene period, which were determined mainly by precipitation-controlled catchment inflow. The mineralogical records also depicted fluctuations in lake level and hydrochemistry on decadal and centennial scales.

Da Qaidam Salt Lake, northern Qaidam Basin, is known for its liquid and solid boron resource. More than that, pinnoite-bearing sediments, occurring in this lake, are rare in the world. However, little attention has been paid to the hydro-climate change and brine evolution correlation with the formation of pinnoite deposit. According to the multi-proxy records, as well as AMS 14C dating, the sediment profiles DCD02 and DCD03 from Da Qaidam Salt Lake were studied. The results revealed that the ore-forming age of three pinnoite deposits are 7.83–8.62 cal ka BP, 6.74–7.07 cal ka BP and 4.66–5.41 cal ka BP. The sedimentary evolution of Da Qaidam Salt Lake along with the pinnoite formation during the past 13,000 years can be divided into four stages, i.e., (1) relatively fresh and deep paleo-lake with low salinity during 12.98–9.00 cal ka BP; (2) seasonal variations between fresh and brackish paleo-lake during 9.00–8.62 cal ka BP; (3) salt lake stage with relatively high salinity and alkalinity during 8.62–4.66 cal ka BP, and (4) relatively shallow lake with high salinity since 4.66 cal ka BP. Under favorable sedimentologic and hydrogeochemical conditions, a series of boron deposits including pinnoite ore formed in different zones of Da Qaidam Salt Lake due to the different ore-forming mechanisms. Finally, under the differential effect of climate warming condition between the high mountain catchments and arid basin, the boron ore-forming model was established as a higher mountain–lower basin–shallower water model.

The physicochemical properties of soils might be affected by the addition of biomass black carbon, a special black carbon produced by incomplete combustion of biomass. Therefore, this study performed experiments to explore the effects of yak dung biomass black carbon (YBC) on physicochemical properties of soils in the northeastern Qinghai-Tibet Plateau. Three YBCs (pyrolyzed at 300, 500, and 700 &deg, C) were separately added into four typical soils with three addition amounts (1%, 5%, and 10%). Changes of soil texture, pH, electrical conductivity (EC), cation exchange capacity (CEC), CHN contents, morphologies, functional groups, and mineral constituents of soils were comparatively studied. The results showed that addition of YBCs affected physicochemical properties of soils. Soil pH, EC, CEC, and carbon/nitrogen content were positively related with addition amount of YBCs. YBC particles were unevenly distributed among soil particles and positively related with addition amount. Addition of YBCs did not change texture, functional groups, and mineral constituents of soils. These results indicated that addition of YBC would be beneficial to stability of the soil ecosystem and sustainability of the northeastern Qinghai-Tibet Plateau.

Mineralogy is very important in the study of lake, especially in the study of regional and past global change using lake sediments. In the final analysis, mineralogy could be involved in the study of the in-depth mechanism of lake sediments. In this paper, analysis the minerals by XRD in the sediments of Toson lake in the northeast of Qinghai-Tibet Plateau, the results showed that the main minerals in Toson lake were aragonite, calcite, quartz, halite, albite, muscovite, clinochlore and dolomite. And the main categories were detrital minerals and carbonate minerals with obvious reverse correlation. It suggested that Toson lake was mainly situated carbonate sedimentary stage, and the input of carbonate was lacustrine authigenic carbonate.

The paper focused on heavy metal (Cr, Cu, Pb, Zn, As, Co, Ni and Mn) concentrations from surface sediment in the southeastern Da Qaidam Salt Lake. Based on the pressed powder pellet method and X-ray fluorescence spectrometry analysis, as well as the enrichment factor, geoaccumulation index and potential ecological risk index, the possible sources and pollution level of heavy metals were studied. The results showed that spatial distributions of heavy metal concentration were indicative of nonuniform characteristics in different zones of Da Qaidam Salt Lake, the average enrichment level of heavy metals followed the decreasing order: EF(As) > EF(Mn) > EF(Cu) > EF(Zn) > EF(Pb) > EF(Cr) > EF(Ni) > EF(Co), and arsenic was the main heavy metal contaminant. In a word, the level of heavy metal pollution in the southeastern Da Qaidam Salt Lake was not strong, but anthropogenic emissions would become the main source of heavy metals along with the frequent and strong human activities in the surrounding region.

An integrated analysis has been carried out on core dated by qualitative X-ray fluorescence core scanning combination of quantitative ICP-AES in order to characterize the extent of elements Cd, Cr, Cu, Zn, and Pb in the Lake Toson in the northeastern Tibet Plateau. When combining both the quantitative and qualitative measurements, we observed a significantly positive correlation. Comparing the ratios between element intensities and concentration, we found that the XRF element intensities were related to the amount of water. Using the intensity of Cl as an indicator of water content, the element intensities of Cd, Cr, Cu, Zn, and Pb in the core samples were corrected. The correlation coefficients of each pairs of the two datasets among Cd, Cr, Cu, Zn, and Pb were significantly raised. These data sets with highly correlations were used to produce a transfer function to relate XRF element intensity with element concentration. Calculated element concentrations from the intensities show only minor differences from concentrations obtained by ICP-AES, indicating XRF core scanners are a very useful tool for measuring element concentration in lacustrine sediments.

The pinnoite deposit occurred in the lakebed of Da Qaidam Salt Lake in Qaidam Basin is rare in the world. This study focused on the pinnoite, ulexite and hydroboracite from Da Qaidam Salt Lake, through multi-index methods including mineralogy and geochemistry, aiming to interpret the mechanism of pinnoite and other borate minerals. The results showed that pinnoite as well as ulexite and hydroboracite in lakeside are formed in the lake environment with specific hydrogeochemical conditions (e.g., alkaline brine, hydrochemical types, boron concentration, boron ions, Mg/Ca ratio, dilution and mixing mechanism). The borate formation was controlled by a coupling mechanism, i.e., the inherent geochemical characteristics and the external conditions.

The paper focused on the study of detrital yellow layer from sediment profile D3 of DaQaidam Salt Lake, based on AMS 14C chronologic and mineralogical methods, aimed to discuss the dust storm events recorded by detrital yellow layer of DaQaidam region since Late Glacial period. The results showed that the grain-size distribution curve displayed double kurtosis, the main peak (10 µm in average) reflected the fine-grained fractions into lake by fluviation, and the secondary peak (> 32 µm) reflected the coarse silt fractions into lake by wind effect and fluviation. Finally, the coarse-grained fractions (> 64 µm) from sediment profile D3 probably recorded the dust storm events since Late Glacial period.

Using an X-ray Fluorescence (XRF) core scanner with nondestructive and successive, the chemistry features of lacustrine sediment can be measured directly. This method of XRF core scanner measurements has been widely applied to core sediment analysis but uncertain of the precision and accuracy. Comparison of intensities obtained by XRF core scanning and the concentration measured by conventional X-ray Fluorescence, indicates effects of physical properties varied from different elements on elemental intensities in the lacustrine sediments of a core from Lake Hurleg in the northeastern Tibetan Plateau. Correlation among elements Ti and Sr between the two measurement methods of the XRF and the conventional XRF is high. Using the intensity of Cl as an indicator of water content, the element intensities of Ti and Sr in the core samples is corrected. But the correlation coefficients of Ti and Sr is litter raised. The results show that XRF core scanning is a very useful tool for measuring element concentration in sediments particularly for high intensities elements.

Environmental changes influenced by human activities were recorded in the sediment cores from Xingyun lake. Based on the 137Cs and 210Pb dating, multi-proxy records, enrichment factor (EF), and geoaccumulation index (Igeo) methods, the history of human–environment interactions in Xingyun lake catchment during the past 140 years was studied. The results showed that the total heavy metal pollution in Xingyun lake followed the decreasing order: the northwestern > the middle > the southwestern > the southern > the north easterly. These distributions were controlled by regional geochemical background values, pollution load, and the lake current driven by prevailing southwesterly winds. The total EF value of heavy metals followed the decreasing order: EF (Zn) > EF (Cr) > EF (Pb) > EF (Cd) > EF (Cu). The total Igeo value of heavy metals also followed the decreasing order: Igeo (Zn) > Igeo (Cr) > Igeo (Pb) > Igeo (Cd) > Igeo (Cu). Consequently, the total pollution level of heavy metals followed the decreasing order: Zn > Cr > Pb > Cd > Cu. Before 1910 AD, the natural erosion caused by climate changes was the key factor for the heavy metals accumulated. After 1910 AD, the heavy metal concentrations were mainly controlled by anthropogenic impacts, the dominant sources were from industrial pollution, agricultural pollution, mining, and organic degradation. Finally, the sedimentary evolution history of Xingyun lake can be divided into four stages, i.e., (1) natural evolution stage during 1862–1910 AD, (2) anthropogenic disturbance stage during 1910–1953 AD, (3) anthropogenic reconstruction stage during 1953–1984 AD, and (4) eutrophication stage after 1984 AD.

Mg-borates were traditionally thought to be diagenetic products of other primary borate minerals. Here we report results from the study of pinnoite deposit from DaQaidam saline lake, indicating that pinnoite minerals are primary in origin. Within the detecting limit of X-ray powder diffraction analysis (XRD) analysis, no other borate minerals than pinnoite are detected from the Mg-borate deposit. The cemented pinnoite orebody shows the sedimentary structure of light-dark lamination couplets, which signal marked seasonal variations in brine chemistry. The scanning electronic microscopy coupled with an energy dispersive X-ray spectrometer (SEM-EDX) examination reveals that all pinnoite minerals displayed euhedral, giving no indication of diagenetic origin. A marked shift in lithology from clastic sediment to evaporitic deposit reflects a critical change in sedimentation regime associated with abrupt changes in hydroclimatic conditions. The deposition of the pinnoite ore-layer containing abundant hydromagnesite marked the beginning of the evaporite formation and the end of the clastic deposition. This suggests that aridification occurred abruptly and the saline lake was much more alkaline than today in the early-stage of the evaporite deposition. The intensified summer evaporation and seasonal variations in water chemistry brought about a shallow to nearly desiccated paleo-lake with pH exceeding 9.3, Mg/Ca ratio &gt, 39, and boron concentration &gt, 600 mg/L, which favored pinnoite precipitation and the formation of pinnoite deposit in the central DaQaidam saline lake.

Qaidam Basin is a hyperarid inland basin with an area of 121 × 10 3 km 2 located on the northern Tibetan Plateau. Today, one fourth of the basin is covered by playas and hypersaline lakes. Nearly 80% of brine lithium found in China is contained in four salt lakes: Bieletan (BLT), DongTaijinaier (DT), XiTaijinaier (XT) and Yiliping (YLP). In the past decade, great attention was paid to improving the technology for the extraction of lithium from the brine deposits, but studies on origin and mode of formation of the brine deposits remained limited. Our recent investigations found that: (1) ~ 748.8 t of lithium was transported annually into the lower catchment of the four salt lakes via the Hongshui–Nalinggele River (H–N River), the largest river draining into the Qaidam Basin, (2) Li + -rich brines are formed only in salt lakes associated with inflowing rivers with Li + concentrations greater than 0.4 mg/L, and (3) the water Li + concentration is positively correlated with both the inflowing river and the associated subsurface brine, including saline lakes with low lithium concentrations. These findings clearly indicate that long-term input of Li + from the H–N River controls the formation of lithium brine deposits. Here we determine that the source of the lithium is from hydrothermal fields where two active faults converge in the upper reach of the Hongshui River. The hydrothermal fields are associated with a magmatic heat source, as suggested by the high Li + and As 3 + content water from geysers. Based on the assumption of a constant rate of lithium influx, we estimate that the total reserves of lithium were likely formed since the postglacial period. Our data indicate that lithium reserves in each of the four salt lakes depend on the influx of Li + -bearing water from the H–N River. The data also suggest that during the progradation of the alluvial Fan I, the H–N River drained mostly into the BLT salt lake until the Taijinaier River shifted watercourse to the north and began to feed the salt lakes of the DT, XT and YLP, alongside with the Fan II progradation. The inference is consistent with stratigraphic evidence from the sediment cores of the four salt lakes. One of the major findings of our work is the importance of the contrasting hydroclimatic conditions between the high mountains containing ice caps and the terminal salt lakes. The greater than 4000 m of relief in the watershed enables a massive amount of ions, such as K + , to be weathered and transported together with detrital material from the huge, relatively wet alpine regions to the hyperarid terminal basins, where intense evaporation rapidly enriches the lake water, resulting in evaporite deposition and associated K + - and Li + -rich brine deposits.

The deep, tight gas reservoir in the Daqing oil field, P. R. China has multiple parallel sandy conglomerates with horizontal heterogeneity and poor historical production from vertical wells and single-lateral horizontal wells. These blocks comprise a large volcanic gas reservoir, which is also challenging for directional drilling. This paper describes a dual-lateral completion with hydraulic fracturing that addresses these production issues. To deploy a stacked dual-lateral well in this reservoir, the deep well depth and its high temperature are considered. The junction must be sealed because of the borehole stability and gas. Re-entry to both laterals, temporarily isolation of laterals, openhole multi-stage hydraulic fracturing and commingled production was possible with a multilateral completion system. This was the operator's first installation of this technology. As a result of comprehensive study, the TAML Level 4 Hook Hanger Multilateral System and One-trip Open Hole Multi-stage Frac System were selected. The junction was successfully cemented after installation of the Hook Hanger System. Each lateral was installed with more than 10 stages of frac system completion tools. After both laterals were hydraulically frac and flow tested, the commingled upper completion string was installed for commercial production. The application of multilateral technology in this field was completed safely. Gas production rates from the multilateral well tested 4.3 times greater than the average production rate from the three offset vertical wells. The absolute open flow rate achieved was more than 1MMSCM, which is the biggest producer for tight gas reservoir in Daqing area. This production rate indicated that the dual-lateral well fracture completion method was applicable for this reservoir.

CO 2 Top-of-Line Corrosion (TLC) of carbon steel pipelines is a serious problem for wet gas transportation. We have studied the corrosion behavior of novel 3%Cr (3Cr) pipeline steel and conventional carbon steel (X70) in the simulated CO 2 TLC environment. The composition and morphology of the corrosion scale are characterized by X-ray diffraction, energy dispersive X-ray spectroscopy and scanning electron microscopy analyses. The results indicate that 3Cr pipeline steel shows superior resistance to CO 2 TLC, exhibiting uniform corrosion with duplex corrosion layer, while X70 suffers severe localized corrosion. It was suggested that the inner Cr enriched layer enhanced the protective ability of the scale to steel substrate and improved the resistance to localized corrosion in CO 2 TLC environment.

Development blocks around Daqing, P.R. China are challenging directional drilling applications. Xushen comprises the largest volcanic gas reservoir in the Ying Cheng formation among 5 development blocks. The formations are hard and abrasive and include a volcanic basement of rhyolite, tuff and breccia with unconfined compressive strength (UCS) up to 30 kpsi. Polycrystalline Diamond Compact (PDC) bits experience high vibrations and premature wear and bit ring-outs. Overall, PDC performance results in short footage and very low rates of penetration (ROP). For a decade, heavy-set roller cones, IADC 617 to 637, were believed to be the correct alternative to drill this hard, heterogeneous formation. However, roller-cone bits are slower than PDC bits and have a limited bearing life. A detailed engineering analysis was undertaken to increase both the penetration rate and distance drilled. As a result of this study, a hybrid bit which combines the advantages of a fixed-cutter and roller-cone was employed to drill in this application. The PDC portion of the hybrid bit design also included a new cutter edge geometry to reduce spalling and impact damage observed on historical PDC runs. The first run in the Ying Cheng group increased ROP by a record 115%, with nearly two times the distance drilled compared to roller-cone bits in the same section. This revolutionary new bit and cutter technology improved reliability and increased drilling efficiency for the duration of the project. After the introduction of this new hybrid bit to the drilling campaign, the operator performed 16 bit runs and saved multiple runs per section. This paper presents a case study of the hybrid bit runs in both the directional and horizontal sections on the wells in northeast China. The detailed analysis of the drilling data also presents the economic benefits of the project and the potential impact of the new technology for the industry.

To study the immunosuppression effect on the thymus of muscovy ducks after infected with muscovy duck reovirus (MDRV) and H9 influenza virus (AIV).After 8-day-old birds were infected with MDRV or H9 AIV, or both, the morbidity and mortality were totaled, the morphology and ultra-structure of the thymus were observed, proliferation ability of thymus cell were detected and the virus distrubition were detected by RT-PCR.After H9 AIV infection, The morbidity was low (10%) and without death. No obvious pathological change was observed on the thymus, whereas the proliferation ability of thymus cell was obviously suppressed. After MDRV infection, The birds grew slow, the morbidity was 80% and mortality was 50%. Thymus was atrophy appearing local necrosis and proliferation ability of thymus cell was obviously suppressed. After co-infection with MDRV and H9 AIV, the birds grew even slower growth. The morbidity was 90% and mortality was 70%. The thymus was atrophy appearing the lymphopenia and local necrosis and proliferation ability of thymus cell was also more obviously suppressed than MDRV infection. Virus duration time and detection ratio in co-infection group were more than in AIV and MDRV group.H9 AIV could lead to minor immunosuppression and MDRV could cause serious immuno-suppression. H9 AIV could aggravate the immunosuppression of thymus after co-infected with MDRV, so MDRV and H9 AIV infection had synergic effect on immunosuppression of the thymus.

Intra-product specialization affects service trade mainly through service outsourcing. Based on Input-Output Tables of 11 OECD countries, this paper analyses the impact of factors, which includ intermediate inputs of producer services in manufacturing and service sectors, labor cost of producer services, and the development level of information, communication &technology level, on the competitiveness of trade of service. Policy recommendation is also provided.

CO2 gas has low viscosity, flows very freely and is corrosive. This paper presents two innovative and economical anti-corrosion techniques of injecting (flooding with) CO2 under conditions of high temperature, high pressure and the CO2 cause corrosion. The down hole packer was fabricated with the CO2 corrosion resistant chrome-plated alloy steel. Chromium is one of the most hard metal and corrosion resistant material, the equipments and devices down hole were chrome-plated that can be also wear-resistant effect. and the general rubber design. The casing tubing annulus injected the imidazoline type corrosion inhibitor to keep the pressure balancing, anti-corrosion situation to protect tubing pipes and casing pipes. This anti-corrosion technique of injection well in CO2 flooding ensured the packer seal long-term security and achieved the CO2 gas safety injection.

The transfer of international manufacturing capital can usually bring higher technology for the local industries. It is helpful to enhance the technology of local firms and formulate independent innovative capacity, if they can form industrial linkage with the international manufacturing capital. This paper constitutes a two-stage optimization industrial linkage model to suggest that in the initial stage, the relationship between local firm's establishing industrial linkage with international manufacturing capital and local economic development is U-curve, but in the second stage, the relationship is inverse U-curve. In the long run, the government should take actively fostering local firm's independent innovative capacity as the policy aim. Otherwise, in the ceaseless rounds of international manufacturing capital transfer, local forms will be gotten into the industrial linkage trap.

In recent years, international manufacturing capital transfers toward Chinese eastern region constantly, and brings a wonderful opportunity for the enterprises in these regions to form industrial linkage with the international manufacturing capital, enhance their independent innovative capacity, and upgrade the industrial structure. But from empirical analysis, the main cause of the transfer is the lower investment cost and the potential of Chinese local market. Once the international manufacturing capital start to operate in gear, they will consider to lower their production cost further to gain their investment return. The practical choice is to form industrial linkage with them. But according to the theoretical analysis, if the native investment cost rises or local markets are saturated, investments are withdrawn, the international manufacturing capital may decline or transfer again. The special investments of the local enterprises will suffer sunk loss, without their independent innovative capacity. There may be an empty space of industry in these regions. Because the local enterprises have no reason to be responsible for the empty space of industry, local governments should adjust the policies of absorbing-fund and investment, turn the policy of absorbing the external fund to the policy of supporting local enterprises to form linkage with local main industry, and advance the independent innovative capacity of local industry to optimize the linkage.