Bis(2,2′-bipyridine)bis­{μ3-cis-N-(2-carboxyl­atophen­yl)-N′-[3-(dimethyl­amino)prop­yl]oxamidato(3−)}­bis(per­chlorato)­tetra­nickel(II) methanol disolvate

In the title methanol disolvate complex, [Ni4(C14H16N3O4)2(ClO4)2(C10H8N2)2]·2CH3OH, the neutral tetra­nickel(II) system lies on a centre of inversion. The polyhedron around each Ni(II) atom is a square pyramid. The separations of the Ni atoms bridged by the oxamide and carboxyl groups are 5.227 (9) and 5.268 (6) Å, respectively. In the crystal structure, a two-dimensional supramolecular network structure involving O—H⋯O and C—H⋯O hydrogen bonding is observed

Study on the Couple of 3D Geological Model and Reservoir Numerical Simulation Results

Taking Dongying Formation, Palaeogene, B Oilfield in Bohai Bay Basin as an example, this paper discusses research on coupling 3D geological model and reservoir numerical simulation results during oilfield development. 3D geological modeling technology and reservoir numerical simulation plays important roles in oilfield development nowadays. 3D geological modeling integrates the static information and data from cores, logs and seismic to approach the reality of reservoir as much as possible. Numerical simulation based on geological models, provides a way to use dynamic data by history matching production. Thus, static data from the subsurface reservoir and dynamic data from production are synthesized with the combination of 3D geological modeling and numerical simulation. At present, except upscaling, which connected these two steps, modeling and simulation are usually discussed and operated separately. This paper tried to find an approach to realize the couple of 3D geological modeling and reservoir numerical simulation, which admits the uncertainty of the geological model and emphases the use of simulation result to adjust geological model. 3D geological modeling provides reservoir numerical simulation with initial reservoir static parameter. With the initial geological knowledge, history matching is conducted to quantitatively describe the flowing rule of oil-water. During the process of matching production history, the changes of reservoir parameters may put insight on corresponding geological knowledge. Based on these updated geological knowledge, these possible changes are coupled to the new geological model. 3D geological model of B oilfield was studied as an example in this paper，how to sufficiently integrate numerical simulation results was researched to improve geological knowledge on the connectivity relationship between well groups, then the 3D geological model was updated

Comparison and correction of element measurements using qualitative and quantitative X-ray fluorescence in lacustrine sediments: A case study of Lake Hurleg

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

The dust storm events recorded in DaQaidam region of Qaidam Basin since Late Glacial period: evidence from the grain size of lake sediment

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

Lithostratigraphy, mineralogy and the boron-bearing brine evolution of DaQaidam Salt Lake in Qaidam Basin since Holocene period, northern Qinghai-Tibet Plateau

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

Effects of Yak Dung Biomass Black Carbon on the Soil Physicochemical Properties of the Northeastern Qinghai-Tibet Plateau

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 degrees 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

Pinnoite Deposit in DaQaidam Saline Lake, Qaidam Basin, China: Hydroclimatic, Sedimentologic, and Geochemical Constraints

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 >39, and boron concentration >600 mg/L, which favored pinnoite precipitation and the formation of pinnoite deposit in the central DaQaidam saline lake