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Water pollution caused by dye is a serious challenge. Herein, we use a novel discharge process to functionalize carbon nanotube (CNT) by COOH groups to form CNT30 for removing methyl red (MR) from water. By pristine CNT, 75% MR is removed in 60 min, with an adsorption capacity of 68.44 mg g-1. By CNT30, 85% MR is fast removed in only 5 min, and the removal efficiency reaches to 95% after 30 min, with an adsorption capacity of 80.33 mg g-1. Thus, a higher MR removal efficiency is achieved in a much shorter time on CNT30. Moreover, CNT30 has an outstanding reusability, with the MR removal efficiency decreasing by only 7% after ten cycles. The COOH groups on CNT30 improve the hydrophilicity of CNT30, thus promoting the interaction of MR in water with CNT30. The hydrogen bonding and electrostatic interaction of MR with the COOH groups on CNT30 could be the force to drive MR adsorption on CNT30. The higher COOH content could be the origin for the better performance of CNT30 in removing dye from water. The discharge process developed herein is operated in O2, without using harmful substances, and the COOH content on CNT can be efficiently tuned by simply changing discharge time. This is different from the chemical modification widely used to functionalize CNT by strong oxidants, e.g., HNO3. The present work is of great significance to realize green construction of materials for more efficiently removing dye from water.

Exploiting geothermal resources, especially hot dry rock (HDR), is essential to reduce carbon emissions to build an acceptable energy structure. The enhanced geothermal system (EGS) for mining HDR has experienced more than 50 years since it was proposed in 1970, obtaining rich research results and construction experience. It is of great significance to review the EGS history, which includes discussing the project site selection and thermal storage stimulations, summarizing the reasons for the shutdown of demonstration projects, and indicating the key factors restricting EGS development. Based on this, the future development direction of EGS is clarified, which can help explore deep geothermal energy and construct associated demonstration projects in China. The overall development of EGS is divided into two stages, namely, the research and development stage before 2000 (a total of 14 EGS projects) and the demonstration and quasi-commercialization stage since 2000 with a rapid development speed (a total of 27 EGS projects). By the end of 2021, the cumulative number of EGS worldwide has increased to 41. However, the cumulative installed capacity of power generation only reaches 37.41 MW. EGS is still on the learning curve, resulting in a long way to go to realize the large-scale commercialization of HDR geothermal energy. The factors restricting the commercialization of EGS are the lack of policy support and capital investment, the limitations of technical difficulty, and the unpredictability of the geological condition of the thermal reservoir, which weakens EGS development and even causes its suspension or termination. Because of the complex geological environment of thermal reservoirs, the fracture network and associated reservoir quality induced by hydraulic stimulations are uncontrollable, causing the fractured quality of the thermal reservoir to be lower than its critical value. It results in numerous adverse problems in most EGS projects, including insufficient thermal reservoir volume, an unstable fracture network, associated heat exchange area, severe fluid loss, and induced unacceptable earthquakes. Thus, the fundamental reason for EGS’s inability to commercialize is that it is challenging to form a reproducible thermal reservoir stimulation model induced by the difference in thermal reservoir geological conditions and the dependence of the existing stimulation technologies on the in situ reservoir geological environment. Establishing the database of HDR and EGS plays an urgent role in EGS development by forming an accurate quantitative system of reservoir geological conditions to explore the relationship between geological conditions and reservoir reconstruction and then build a replicable thermal reservoir reconstruction technology. Focusing on new and demonstration stimulations for the thermal reservoir, such as the enhanced geothermal system based on caving technology (EGS-E), FORGE, and DEEPEGS projects, may provide an acceptable way to break through the dependence of thermal reservoir stimulation on in-situ geological conditions and form the “reproducible” deep-geothermal resource mining system to realize the large-scale commercialization of deep-geothermal resources.

Abstract Colorectal cancer (CRC) is a major malignancy threatening the health of people in China and screening could be effective for preventing the occurrence and reducing the mortality of CRC. We conducted a multicenter, prospective clinical study which recruited 4,245 high‐risk CRC individuals defined as having positive risk‐adapted scores or fecal immunochemical test (FIT) results, to evaluate the clinical performance of the multitarget fecal immunochemical and stool DNA (FIT‐sDNA) test for CRC screening. Each participant was asked to provide a stool sample prior to bowel preparation, and FIT‐sDNA test and FIT were performed independently of colonoscopy. We found that 186 (4.4%) were confirmed to have CRC, and 375 (8.8%) had advanced precancerous neoplasia among the high CRC risk individuals. The sensitivity of detecting CRC for FIT‐sDNA test was 91.9% (95% CI, 86.8–95.3), compared with 62.4% (95% CI, 54.9–69.3) for FIT (P

Carbon-based materials, metal oxides and metal nanoparticles have been widely used in propellants, explosives and pyrotechnics. Cold plasma technique has been developed for material fabrication and modification at temperatures lower than 200 ⁰C. Due to the low temperatures, cold plasma can efficiently modify material surface properties, and simultaneously maintain material structures well, especially for temperature-sensitive materials. Cold plasma applies gas, e.g. Ar, N2, O2, H2 and air, as working gas, without any harmful substance like acid, alkali and organic solvent. Moreover, material surface properties can be efficiently tuned by simply changing plasma properties, e.g. power, time and working gas. The present review discusses recent progresses in using cold plasma to fabricate carbon-based materials, metal oxides and metal nanoparticles, and to modify surface properties of carbon-based materials, metal oxides and metal nanoparticles. Future research opportunities and challenges are also proposed. It is believed that the present review will stimulate more studies on material fabrication and modification by cold plasma, and help to construct more efficient materials for propellants, explosives and pyrotechnics.

Electrocatalytic glucose oxidation reaction (GOR) is the key to construct sophisticated devices for fast and accurately detecting trace glucose in blood and food. Herein, a noble-metal-free Cu/C-60 catalyst is fabricated by supporting Cu2O-CuO nanoparticles on carbon nanotubes through a novel discharge process. For GOR, Cu/C-60 shows a sensitivity as high as 532 μA mM−1 cm−2, a detection limit as low as 1 μM and a steady-state response time of only 5.5 s. Moreover, Cu/C-60 has outstanding stability and anti-interference ability to impurities. The synergistic effect of Cu2O-CuO could improve the adsorption and conversion of glucose, thus enhancing GOR performance. By using Cu/C-60, we fabricate a three-electrode chip. A portable and compact electrochemical system is constructed by connecting the three-electrode chip with Cu/C-60 to an integrated circuit board and a mobile phone for recording and displaying data. The portable and compact electrochemical system results in a GOR sensitivity of 501 μA mM−1 cm−2, which is close to the data measured on the bloated electrochemical workstation. The detection limit of the portable and compact electrochemical system in GOR is 50 μM. This is higher than those obtained on the bloated electrochemical workstation, but is much lower than the common blood glucose concentration of human body (>3 mM). This demonstrates the accuracy, reasonability and applicability of the portable and compact electrochemical system. The results of the present work are helpful for fabricating fast, efficient and portable devices for detecting trace amount of glucose in blood and food.

Photocatalytically reducing CO2 by H2O into valuable carbon-containing chemicals is one of the greatest concerns for both scientific and industrial communities, due to its great potential in solving energy and environmental problems. However, the photocatalytic reduction efficiency is still much lower than the need of large-scale applications. Abilities of photocatalysts in adsorbing CO2 and splitting H2O to produce protons are crucial factors determining the photocatalytic reduction efficiency. Significant research efforts have been devoted to addressing the issues on CO2 adsorption and proton production. The present review discusses the recent progresses in improving CO2 adsorption and proton production on photocatalysts for increasing the photocatalytic reduction efficiency. Future research opportunities and challenges are also discussed. It is hoped that the present review can stimulate more deep insights on adsorption of CO2 and production of proton for increasing the photocatalytic reduction efficiency.

The generation of bound electron and hole pairs—excitons—is a key process in photovoltaic technologies, yet it is challenging to follow their initial dynamics. Here, Luoet al. probe the Rydberg eigenstates that characterize the excitonic transport and coherent conversion in a perovskite material.

Histone H2B monoubiquitination is a key histone modification that has significant effects on chromatin higher-order structure and gene transcription. Multiple biological processes have been suggested to be tightly related to the dynamics of H2B monoubiquitination. However, a comprehensive understanding of biological roles of H2B monoubiquitination is still poorly understood. In the present study, we developed an efficient tool to disrupt endogenous H2B monoubiquitination levels by using an H2BK120R mutant construct expressed in human cells. Genome-wide microarray analysis of these cells revealed a potential global view of biological functions of H2B monoubiquitination. Bioinformatics analysis of our data demonstrated that while H2B monoubiquitination expectedly affected a number of previously reported biological pathways, we also uncovered the influence of this histone modification on many novel biological processes. Therefore, our work provided valuable information for understanding the role of H2B monoubiquitination and indicated potential directions for its further studies.