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Monolayer transition metal dichalcogenides (TMDs) have drawn significant attention for their potential applications in electronics and optoelectronics. To achieve consistent electronic properties and high device yield, uniform large monolayer crystals are crucial. In this report, we describe the growth of high-quality and uniform monolayer WSe2 film using chemical vapor deposition on polycrystalline Au substrates. This method allows for the fabrication of continuous large-area WSe2 film with large-size domains. Additionally, a novel transfer-free method is used to fabricate field-effect transistors (FETs) based on the as-grown WSe2. The exceptional metal/semiconductor interfaces achieved through this fabrication method result in monolayer WSe2 FETs with extraordinary electrical performance comparable to those with thermal deposition electrodes, with a high mobility of up to ≈62.95 cm2 V−1 s−1 at room temperature. In addition, the as-fabricated transfer-free devices can maintain their original performance after weeks without obvious device decay. The transfer-free WSe2-based photodetectors exhibit prominent photoresponse with a high photoresponsivity of ~1.7 × 104 A W−1 at Vds = 1 V and Vg = −60 V and a maximum detectivity value of ~1.2 × 1013 Jones. Our study presents a robust pathway for the growth of high-quality monolayer TMDs thin films and large-scale device fabrication. [ABSTRACT FROM AUTHOR]

The twenty-first century is a new century in ocean development and utilization. With increasing attention paid by the government, geological marine surveys, in particular geological marine analysis and testing technology has gained significant progress. The latest progresses on China′s geological marine analysis and testing technology is briefly summarized in this paper. Progress is listed as follows: establishing a fast and efficient systematic method for simultaneous multi-element analysis of geological marine samples by large analytical instruments, in order to meet the demand of regional geological marine surveys and geological coastal surveys; establishing and expanding test technology of anomaly identification and application for gas hydrate samples，including the methods of rapid qualitative tests on anions (Cl-, Br-, SO42-) and cations (Na+, NH4+, K+, Ca2+, Mg2+) in pore water by ion chromatography, and new detection technologies on natural gas hydrate simulated experiments based on ultrasonic, resistance and time domain reflectometry (TDR). Establishing an integrated method for organic pollutant samples in marine sediments to simultaneously purify, separate and test, which mainly applies a composite SPE column to separate and uses C6H14 and C6H14/CH2Cl2 solution to leach, so as to effectively retain the substrate impurity and thus significantly improve the test efficiency is also summarized. In addition, other progresses are also introduced, such as ocean mineral sample analysis technology, geological marine reference material development and ship-carried and in-situ chemical detection technology. It is speculated that the ship-carried and in-situ testing technology in the marine investigation and monitoring will become more and more important, and that strengthening the performance of marine chemical sensors and detection of integrated technology is an important development direction in the future.

Two new isoflavones (1 and 2), as well as eight known ones were isolated from the roots of Sophora tonkinensis Gagnep. Compound 1 represents an unprecedented polymerization pattern constructed by isoflavone and cytisine. Their structures were elucidated by comprehensive spectroscopic data analysis, combined with ECD calculations. Compound 1 displayed significant anti-tobacco mosaic virus (TMV) activity compared with the positive control ningnanmycin. Moreover, compound 6 exhibited potent α-glucosidase inhibitory activity with IC50 value of 47.4 mg/L. [ABSTRACT FROM AUTHOR]

Two new dibenzocyclooctane lignans, schisanwilsonins H (1) and I (2), together with eight known compounds gomisin J (3), wulignan A1 (4), gomisin S (5), tigloylgomisin P (6), gomisin O (7), (-)-gomisin K1 (8), rubschisantherin (9) and wuweizisu C (10) were isolated from the 95% ethanol extract of the fruits of Schisandra wilsoniana. 7 exhibited anti-HBV activity with potency against HBsAg and HBeAg secretion by 37.1% and 32.6%, respectively, at 50 μg/ml. 10 exhibited anti-HIV activity with EC50 and therapeutic index (TI) values of 2.10 μg/ml and 11.98, respectively. [ABSTRACT FROM AUTHOR]