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Exploration practice has proved that deep and ultra-deep reservoirs consist of mainly matrix-porous dolomite reservoirs and fractured-vuggy karst reservoirs and still will be very important targets for future exploration, in which large oil and gas fields such as Anyue, Yuanba, Halahatang, Fuman and Shunbei have been discovered. This paper systematically summarizes three theoretical and technical achievements in studying deep and ultra-deep carbonate reservoirs in the past decade. (1) The micro-zone and multi-parameter experiment analysis technology featured by determining the "age, temperature, pressure and fluid properties" of carbonate reservoirs, together with experimental simulation of cross-tectonic-period pore formation and preservation featured by the "multi-stage, continuous, visualized and online detection technology", providing useful tools for studying the pore formation and preservation mechanism of deep and ultra-deep carbonate rocks from the perspective of "forward" and "inversion". (2) Deep and ultra-deep matrix-porous dolostone reservoirs are still controlled by sedimentary facies, among which reef (mound) and/or beach contribute most. The reservoir space is mainly composed of sedimentary primary pores and supergene dissolution pores and fractures, though some of reservoir spaces are formed by burial dissolution and they tend to develop and may locally concentrate following the pre-existing porous zone. In other words, burial dissolution vugs are inherited rather than newly formed. Early dolomite precipitation (or dolomitization) has a high potential to preserve early pores. (3) The development and preservation mechanism of fractured-vuggy karst limestone reservoirs in deep and ultra-deep realm was analyzed. Pene-contemporaneous dissolution and interlayer and buried-hill karstification control the development of early and late supergene fractured-vuggy reservoirs. Strike-slip faults superimposed with supergene karstification lead to the development of "fence-style" faulted karst reservoirs. Dissolution simulation experiments reveal that the development of karst fracturedvuggy reservoirs is facies-controlled in certain degree, mainly developed in packstone. Rock mechanics analysis reveals that the preservation of caves is under the control of lithology, cave size, and the distance to the unconformity, and caves can be well preserved at 10,000 m. The theoretical and technical achievements provide supports for carbonate oil and gas exploration into ten thousand meters deep. [ABSTRACT FROM AUTHOR]

The age and dolomitization processes in the Paleo-oil reservoir zone, which is composed of massive dolostones found in the Qiangtang Basin (SW China), are still debated. In this research, the Long'eni-Geluguanna Area was selected. Macroscopic information, thin sections, and geochemical methods were used to investigate the dolomitization characteristics and the processes that controlled dolomitization. Five types of replacive dolomites and two types of dolomite cement were observed. Some of the dolomites displayed ghosts of primary sedimentary structures. Saddle dolomites were prevalent, occurring in the interparticle and moldic pores of the limestone which should have been filled at an early diagenetic stage. Ten microfacies types were identified. The foraminifera assemblage provides evidence that the studied interval is of Early Jurassic age. The δ13C values are similar to the contemporaneous seawater signature. The REE+Y patterns of limestones and dolostones exhibit similarities to that of seawater. The mean Na and Sr values are comparable to those of other near-normal seawater dolomites. The δ18O values of all lithologies are markedly depleted. The dolomitization started penecontemporaneously, with deposition. A general sand shoal setting with patch reefs developed. The dolomitizing fluids, near-normal seawater, was probably formed by slight evaporation on top of the shoal. Saddle dolomites in the interparticle and moldic pores might indicate hydrothermal activity, which also caused the recrystallization of some pre-existing dolomites. The recrystallization might have slightly increased the crystal size, demolished the ghost structures, formed saddle dolomites, and altered the REE+Y patterns. The recrystallization extent diminished with increasing distance from the fluids-providing fracture. Furthermore, the existence of protected areas within the sand shoal settings could enhance the vertical and horizontal heterogeneity of dolostone reservoirs. [ABSTRACT FROM AUTHOR]

What is known and objective: To analyse the diagnostic accuracy of bronchoalveolar lavage fluid galactomannan (BALF‐GM) assay for invasive pulmonary aspergillosis (IPA) in adults to determine the optimal diagnostic cut‐off by meta‐analysis. Methods: PubMed, Embase, Web of Science, Cochrane Library, China national knowledge infrastructure (CNKI), and China Wanfang databases were searched to collect relevant studies on the diagnostic value of BALF‐GM for IPA from inception to March 2022. The summary receiver operating characteristic (SROC) curve was drawn to determine the optimal diagnostic cut‐off. Results and discussion: Nineteen articles (56 data sets) were included. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 0.79 (95% CI: 0.72–0.84), 0.92 (95% CI: 0.88–0.94), 9.25 (95% CI: 6.84–12.52), 0.23 (95% CI: 0.18–0.30), 39.44 (95% CI: 29.55–52.65), and 0.92 (95% CI: 0.90–0.94), respectively. The area under the curves (AUCs) were 0.92, 0.86, 0.93, 0.89, 0.88, and 0.94 when the cut‐off values were 0.5, 0.8, 1.0, 1.5, 2.0, and 3.0, respectively. Sixteen studies were included in the combined analysis when the cut‐off value was 0.5. The results showed that the pooled sensitivity, specificity, PLR, NLR and DOR of BALF‐GM (cut‐off 0.5) for the diagnosis of IPA were 0.89 (95% CI: 0.83–0.93), 0.79 (95% CI: 0.71–0.86), 4.33 (95% CI: 3.04–6.16), 0.14 (95% CI: 0.09–0.22), and 31.51 (95% CI: 17.43–56.98). The AUC was 0.92 (95% CI: 0.89–0.94). What is new and conclusions: BALF‐GM has excellent diagnostic accuracy for adult IPA, which can be diagnosed early and treated early to reduce the mortality rate. Considering the sensitivity, specificity, PLR and NLR, the recommended diagnostic cut‐off of BALF‐GM for adult IPA is 0.5. [ABSTRACT FROM AUTHOR]

In the title compound, [Fe(C38H38N10)](ClO4)2·CH3OH, the FeII atom has a distorted octahedral coordination environment with four benzimidazol N atoms and two amino N atoms from an N,N,N′,N′-tetrakis(benzimidazol-2-ylmethyl)cyclohexane-1,2-trans-diamine ligand. The uncoordinated solvent methanol molecule is hydrogen bonded to an O atom of a perchlorate anion. One of the perchlorate anions is disordered over two sets of sites with occupancy factors of 0.539 (14) and 0.461 (14). N—H...O and C—H...O hydrogen bonds, as well as π–π stacking interactions between the imidazol rings and between the imidazol and benzene rings [centroid–centroid distances = 3.714 (2) and 3.705 (2) Å] give rise to a three-dimensional network.

Damage-free sputter deposition process has been developed for metal gate complementary metal-oxide-semiconductor technology. A plasma charge trap (PCT) was introduced in order to eliminate high-energy particle bombardment during sputter deposition processes. Molybdenum (Mo)-gated PMOSFETs were fabricated using a conventional gate-first process. It is shown that the PCT technology yields excellent characteristics in current drivability, as well as in gate oxide integrity (GOI) such as gate leakage current and charge-to-breakdown ([Q.sub.BD]). The metal gate was also applied to a nonvolatile memory (NVM), which would require most stringent damage control, and good retention characteristics were demonstrated. Index Terms--Metal gate, molybdenum, sputtering.

A liquid-assisted laser cleaning process is described for removing very small contaminant particles from NiP magnetic hard disk substrates.

Heterostructure phosphor composites have been used widely in the fields of targeted bio-probes and bio-imaging, hyperthermia treatment, photocatalysis, solar cells, and fingerprint identification. The structures, plasmon-enhanced luminescence and mechanism of metal/fluorophore heterostructure composites, such as core–shell nanocrystals, multilayers, adhesion, islands, arrays, and composite optical glass, are reviewed in detail. Their extended applications were explored widely since the surface plasmon resonance effect increased the up-conversion efficiency of fluorophores significantly. We summarize their synthesis methods, size and shape control, absorption and excitation spectra, plasmon-enhanced up-conversion luminescence, and specific applications. The most important results acquired in each case are summarized, and the main challenges that need to be overcome are discussed. [ABSTRACT FROM AUTHOR]