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Reliable observations of aerosol optical properties are crucial for quantifying the radiative forcing of climate. The simultaneous measurements of aerosol optical properties at three wavelengths for PM1 and PM10 were conducted in urban Beijing from March 2018 to February 2022. The aerosol absorption coefficient (σab) at 550 nm of PM10 and PM1 decreased by 55.0 % and 53.5 % from 2018 to 2021. The significant reduction in σab may be related to reduced primary emissions caused by effective air pollution control measures. PM2.5 mass concentration decreased by 34.4 % from 2018 to 2021. Single scattering albedo (SSA) increased from 0.89±0.04 for PM10 (0.87±0.05 for PM1) in 2018 to 0.93±0.03 for PM10 (0.91±0.04 for PM1) in 2021. Increasing SSA and decreasing PM2.5 mass concentration suggest that the fraction of absorbing aerosols decreased with improved air quality due to pollution control measures being taken. The annual average submicron absorption ratio (Rab) increased from 86.1 % in 2018 to 89.2 % in 2021, suggesting that fine particles are the main contributors to total PM10 absorption and that the contribution of fine particles to absorption became more important. The absorption Ångström exponent (AAE) in winter decreased from 2018 to 2021, implying a decreasing contribution from brown carbon to light absorption, which may relate to the reduced emissions of biomass burning and coal combustion. During the study period, aerosol radiative forcing efficiency became more negative, mainly influenced by increasing SSA and was −27.0 and −26.2 W m−2 per aerosol optical depth (AOD) for PM10 and PM1 in 2021. Higher σab and PM2.5 mass concentrations were primarily distributed in clusters 4 and 5, transported from the south and the west of Beijing each year. σab and PM2.5 corresponding to clusters 4 and 5 decreased evidently from 2018 to 2021, which may result from the control of source emissions in surrounding regions of Beijing. The 4-year data presented in this study provide critical optical parameters for radiative forcing assessment within two size ranges and are helpful for evaluating the effectiveness of clean air action.

RAB32 is a potential prognostic marker that is overexpressed in a variety of cancers. The purpose of this study was to investigate the expression and function of RAB32 in glioblastoma (GBM).The expression data of RAB32 were obtained by accessing TCGA, CGGA and GEPIA databases, which were verified by western blot and immunohistochemistry. The prognostic value of RAB32 methylation was carefully examined using cBioPortal and MethSurv. GSEA was used to analyze cancer-related signaling pathways that may be activated by high RAB32 expression. The correlation between RAB32 and GBM immunoinfiltration was studied by accessing TISIDB database.The effects of RAB32 on proliferation, migration and invasion of GBM cells were predicted by Colony Formation Assay, CCK-8 assay and Transwell assay. In this study, RAB32 expression was up-regulated in GBM compared to normal brain tissue. Survival analysis showed that high expression of RAB32 was an independent risk factor for overall survival in glioma patients. RAB32 methylation was negatively correlated with RAB32 expression, and the overall survival rate of RAB32 hypomethylated patients was lower than that of RAB32 hypermethylated patients.Through functional enrichment analysis, we found that the RAB32 overexpression significantly activated multiple signaling pathways. Immunoassay results showed that RAB32 expression was correlated with immune infiltration of tumor microenvironment. Knocking down the expression of RAB32 gene significantly inhibited the proliferation, migration and invasion of glioma cells. Our results show that RAB32 is a key factor affecting the prognosis of patients with GBM, and its targeting may provide a new treatment for patients with GBM.

Mineral dust is a major natural atmospheric aerosol that impacts the Earth's radiation balance. The significant scavenging process of fine particles by the strong wind during the dust provided a relatively pristine environment in which the occurrence of new particle formation (NPF) was less influenced by anthropogenic emissions. In this study, the NPF events occurring after the dust event (dust-related NPF) and other normal days (other NPF events) were classified based on the long-term particle number size distribution (PNSD) in urban Beijing in spring from 2017 to 2021. By comparing the two types of NPF events, we estimated that anthropogenic emissions could contribute approximately 50 % to the observed formation rate and 30 % to the growth rate. Anthropogenic emissions played a more important role when nucleated particles grew into the sizes above 10 nm. We also assessed a severe dust storm that originated from Mongolia and swept over northern China on March 15–16, 2021. The maximum hourly mean PM10 mass concentration reached 8000 μg m-3 during the dust storm. A downward trend of particle hygroscopicity was found during dust storms as compared with the polluted episode, resulting in an increasing trend of the critical diameter at different supersaturations (ss) where aerosols are activated as cloud condensation nuclei (CCN), although NPF occurred at approximately noon time when dust faded. The critical diameter was elevated by approximately 6 %–10 % (ss = 0.2 % and 0.7 %) during the dust storm, resulting in a lower CCN activation ratio, especially at low supersaturation. Modifications of the nucleation and growth process, as well as the particle-size distribution and hygroscopicity by the dust, provide valuable information that reveals the underlying climate and air quality effects of Asian mineral dust.

Reliable observations of aerosol optical properties are crucial for quantifying the radiative forcing of climate. The simultaneous measurements of aerosol optical properties at three wavelengths for PM1 and PM10 were conducted in urban Beijing from March 2018 to February 2022. The results showed considerable reductions in aerosol absorption coefficient (σab) at 550 nm of PM10 and PM1 by 55.0 % and 53.5 % from 2018 to 2021. SSA increased from 0.89 ± 0.04 for PM10 (0.87 ± 0.05 for PM1) in 2018 to 0.93 ± 0.03 for PM10 (0.91 ± 0.04 for PM1) in 2021. These results indicated that the absorbing aerosols were more effectively controlled than scattering aerosols due to pollution control measure-taking. The annual average submicron absorption ratio (Rab) increased from 86.1 % in 2018 to 89.2 % in 2021, suggesting that fine particles are the main contributors to total PM10 absorption and that the fine particles to absorption became more important. Absorption Angstrom exponent (AAE) in winter decreased from 2018 to 2021, implying a decreasing contribution from brown carbon to light absorption, which may relate to the decreased emissions of biomass burning and coal combustion. During the study period, aerosol radiative forcing efficiency became more negative and were −27.0 and -26.2 W m−2 AOD−1 for PM10 and PM1 in 2021, which was mainly influenced by increasing SSA. Higher σab and PM2.5 mass concentrations were mainly distributed in clusters 4 and 5 transported from the south and the west of Beijing in each year. σab and PM2.5 corresponding to clusters 4 and 5 decreased evidently from 2018 to 2021, which may result from the control of source emissions in surrounding regions of Beijing. The 4-year data presented in this study provide critical optical parameters for radiative forcing assessment within two size ranges and are helpful for evaluating the effectiveness of clean air action.

The fracture behavior of the Cu/Sn-3.0Ag-0.5Sn (SAC305)/Cu solder joint was investigated by conducting tensile tests with in situ X-ray micro-computed tomography (μ-CT) observation, and finite element (FE) simulation. The tensile fracture process of solder joints with a real internal defect structure was simulated and compared with the experimental results in terms of defect distribution and fracture path. Additionally, the stress distribution around the defects during the tensile process was calculated. The experimental results revealed that the pores near the intermetallic compound (IMC) layers and the flaky cracks inside the solder significantly affected the crack path. The aggregation degree of the spherical pores and the angle between the crack surface and the loading direction controlled the initiation position and propagation path of the cracks. The fracture morphology indicated that the fracture of the IMC layer was brittle, while the solder fracture exhibited ductile tearing. There were significant differences in the fracture morphology under tensile and shear loading.

The controllability of materials that has attracted widespread attention is a key factor for improving the performance of SERS substrates. Hence, in this study, a kind of controllable materials constructed with Au nano-disk array and monolayer MoS2 had been developed. The optical properties of the composite were studied and the Raman enhancement was obtained. Compared with the monolayer MoS2, the peak of the above composite was slightly red-shifted, and the intensity was increased by about 2.5 times. This was due to the thermal effect and the internal quantum efficiency improvement of MoS2 caused by the local surface plasmon resonance of Au. The simulation results of the finite-difference time-domain and the experimental results all showed an enhanced photoluminescence of the composite, which was attributed to the resonance wavelength of the Au nano-disk being adjusted to be consistent with the photoluminescence peak of the monolayer MoS2. Through the synergistic action of the electromagnetic enhancement and chemical enhancement, the highly sensitive and stable surface-enhanced Raman scattering (SERS) active substrate constructed with Au-MoS2 composite was sequentially utilized in the detection of antibacterial agent residues on the aquatic products. Thereafter, a calibration curve with ultralow limits of detection (LOD) at 10−15 M was established for the standard solutions of crystal violet (CV), and then the assay on shrimps was successfully realized. Therefore, this research provides an effective way for attractive SERS performance of MoS2, and confirms the potential possibility for application on food safety and other trace detection.

In this study, we employed ultrahigh pressure extraction on polysaccharides from Morinda officinalis and evaluated its antioxidant activity. Other two extraction ways as supercritical assisted ultr...

Significance Novel insecticides are developed and implemented in agriculture without a broad understanding of their sublethal effects. Although all act via nicotinic acetylcholine receptors, neonicotinoids and the novel sulfoxaflor insecticide exhibit differences in relative toxicity. In this study comparing the effects of these insecticides on visual motion detection and escape behavior, we show that sulfoxaflor displays decreased sublethal toxicity despite similar lethal endpoints of these insecticides. Imidacloprid reduces putative neural population code variability when responding to approaching objects, suggesting that neonics may constrain the tuning of visual sensory circuits. We suggest that neuroethologic methods are powerful tools to link toxic effects across levels of biological organization and further our understanding of how neural populations operate in complex sensory environments., Insect nervous systems offer unique advantages for studying interactions between sensory systems and behavior, given their complexity with high tractability. By examining the neural coding of salient environmental stimuli and resulting behavioral output in the context of environmental stressors, we gain an understanding of the effects of these stressors on brain and behavior and provide insight into normal function. The implication of neonicotinoid (neonic) pesticides in contributing to declines of nontarget species, such as bees, has motivated the development of new compounds that can potentially mitigate putative resistance in target species and declines of nontarget species. We used a neuroethologic approach, including behavioral assays and multineuronal recording techniques, to investigate effects of imidacloprid (IMD) and the novel insecticide sulfoxaflor (SFX) on visual motion-detection circuits and related escape behavior in the tractable locust system. Despite similar LD50 values, IMD and SFX evoked different behavioral and physiological effects. IMD significantly attenuated collision avoidance behaviors and impaired responses of neural populations, including decreases in spontaneous firing and neural habituation. In contrast, SFX displayed no effect at a comparable sublethal dose. These results show that neonics affect population responses and habituation of a visual motion detection system. We propose that differences in the sublethal effects of SFX reflect a different mode of action than that of IMD. More broadly, we suggest that neuroethologic assays for comparative neurotoxicology are valuable tools for fully addressing current issues regarding the proximal effects of environmental toxicity in nontarget species.

Microbial degradation of chlortetracycline (CTC) is an effective bioremediation method. In the present study, an enrichment technique was used to isolate a Bacillus cereus LZ01 strain capable of effectively degrading CTC from cattle manure. Response surface methodology was used to identify optimized conditions under which strain LZ01 was able to achieve maximal CTC removal (83.58%): temperature of 35.77 °C, solution pH of 7.59, CTC concentration of 57.72 mg/L and microbial inoculum of 0.98%. The antibacterial effect of CTC degradation products on Escherichia coli was investigated by the disk diffusion test, revealing that the products by LZ01 degradation of CTC exhibited lower toxicity than parent compound. Shake flask batch experiments showed that the biodegradation of CTC was a synergistic effect of intracellular and extracellular enzymes, and intracellular enzyme had a better degradation effect on CTC (77.56%). Whole genome sequencing revealed that genes associated with ring-opening hydrolysis, demethylation, deamination and dehydrogenation in strain LZ01 may be involved in the biodegradation of CTC. Subsequent seven possible biodegradation products were identified by LC-MS analyses, and the biodegradation pathways were proposed. Overall, this study provides a theoretical foundation for the characterization and mechanism of CTC degradation in the environment by Bacillus cereus LZ01.

The influence of relative humidity on aerosol properties and the direct radiative forcing of PM

The mechanism of the high hydrostatic pressure (HHP) effect on horseradish peroxidase (HRP) is still unclear. The activity, thermal stability and structural changes of HRP after HHP treatments were studied in this work. Compared with the untreated sample, the enzyme activity reduces by 36% after 800 MPa processing. The results indicated that the conformation of the enzyme active center changes under pressure. Furthermore, HHP also changes the conformation of disulfide bonds and some secondary structures in HRP. These structural and conformational changes induce decreased activity. In addition, differential thermal scanning (DSC) results showed that the thermal denaturation temperature decreased from 103.74 °C to 85.78 °C after pressure treatment, suggesting HRP molecules formed large aggregates after pressure treatment. In this study, the interaction mechanism between pressure and enzyme was studied as well, and the results can provide some guidance for the application of HHP technology in fruit and vegetable products processing.

A hygroscopic tandem differential mobility analyser (H-TDMA) was used to observe the size-resolved hygroscopic characteristics of submicron particles in January and April 2018 in urban Beijing. The probability distribution of the hygroscopic growth factor (HGF-PDF) in winter and spring usually showed a bimodal pattern, with more hygroscopic mode (MH) being more dominant. The seasonal variation in particle hygroscopicity was related to the origin of air mass, which received polluted southerly air masses in spring and clean northwesterly air masses in winter. Particles showed stronger hygroscopic behaviour during heavy pollution episodes (HPEs) with elevated concentrations of secondary aerosols, especially higher mass fraction of nitrate, which were indicated using the PM

Biochar-immobilized microorganism technology is an effective way to remove antibiotic contamination in aqueous solutions. In this study, the effect and mechanism of immobilization of Bacillus subtilis by honeysuckle residue derived biochar for the removal of chlortetracycline(CTC) were investigated using corn straw biochar as a control. The biochar's structural characteristics and properties were determined using scanning electron microscopy, X-ray diffractometer, Fourier transform infrared spectrometer, specific surface area and pore size analyzer. It was found that honeysuckle residue derived biochar had a well-developed pore structure, which provided adequate living space for microorganisms. The removal rate of CTC (50 mg/L) by honeysuckle residue biochar-microbial complex(HBCM) was 15.31% higher than that of corn straw biochar-microbial complex, indicating that HBCM was an excellent carrier. The mechanism of CTC removal by HBCM was a synergistic effect of biochar adsorption and microbial degradation. The removal process of HBCM material was carried out for 3 days at an optimum substrate concentration of 50 mg/L, ambient temperature of 35°C, solution pH of 7 and the addition of 5 g/L complexes, achieving a removal rate of 78.35%. In addition, the complex possessed high storage stability and could be reused three times continuously and efficiently. This study provides a method for preparing an efficient biochar-microbial complex using Chinese medicine residue waste substrate, which provides a new idea for removing CTC from water.

Influenced by the spread of the global 2019 novel coronavirus (COVID-19) pandemic, primary emissions of particles and precursors associated with anthropogenic activities decreased significantly in China during the Chinese New Year of 2020 and the lockdown period (January 24–February 16, 2020), as indicated by approximately 50 % reduction of NOx emission nation-wide based on the open literature. Two-month measurements of the number size distribution of neutral particles and charged ions showed that during the lockdown (LCD) period, the number concentration of particles smaller than 100 nm decreased by approximately 40 % compared to the pre-LCD period in January. However, the accumulation mode particles increased by approximately 20 % as several polluted episodes contributed to secondary aerosol formation. In this study, new particle formation (NPF) events were found to be enhanced in the nucleation and growth processes during the LCD period, as indicated by higher formation (J2) and growth rate (GR), even as NPF occurrence frequency slightly decreased. The condensing vapors controlling the nucleation and growth process, sulfuric acid, and oxidation product of volatile organic compounds were estimated based on available information. The proxy values showed that sulfuric acid and organic oxidized vapors increased during the LCD period by approximately 35 % and 133 % on NPF days, respectively. Higher J2 and GR during the LCD period were favored by the increased concentration level of condensing vapors and decreased condensation sink. Several heavy haze episodes have been reported by other studies during the LCD period; however, the increase in nanoparticle number concentration should also be considered. Some typical NPF events produced a high number concentration of nanoparticles that intensified in the following days to create severe aerosol pollution. Our study confirms a significant enhancement of the nucleation and growth process of nanoparticles during the COVID-19 LCD in Beijing and highlights the necessity of controlling nanoparticles in current and future air quality management.

The aerosol scattering properties of submicron (PM

To evaluate the influence of anthropogenic emission reductions since 2013 in China, a long-term trend analysis of the particle number size distribution (PNSD) and new particle formation (NPF) events in the Yangtze River Delta (YRD) region was conducted based on the PNSD measurement (diameter ranging from 3 to 850 nm) at the Lin'an (LAN) regional background station from 2013 to 2019. A modified Mann-Kendall test and a Theil-Sen estimator were used to calculate the overall trend of particle number concentrations in different modes and the relevant influencing factors. We observed a significant decreasing trend in the Aitken and accumulation mode number concentrations, with annual decrease rates of approximately 5.6% and 8.2%, respectively, resulting in an approximately 6.0% decline in total particles annually. However, the nucleation mode particle number concentration showed no significant trend from 2013 to 2016, but an increasing trend from 2016 to 2019, which was related to the NPF events occurrence frequency. The regional NPF events of “banana shape” accounted for an increasing fraction of all NPF events. As a key parameter influencing the NPF event, the condensation sink decreased by approximately 63% from 2013 to 2019. Moreover, the estimated sulfuric acid concentration decreased by approximately 50%, with a higher reduction rate occurring during 2013–2016 as result of the effective SO2 reduction. Surface meteorological factors (including the air temperature, relative humidity, air pressure, and wind) and the air masses origin were found to played minor roles in the long-term trend of NPF events. As PNSD and NPF events are closely related to changes in the particle emissions and regional air pollution levels, studies concerning PNSD and NPF are necessary to provide important information regarding air quality improvements and evaluating the efficacy of climate change mitigation strategies.

Biochar-immobilized microorganism technology is an effective way to remove antibiotic contamination from water bodies. In this study, three common Chinese medicine residues (forsythia, erding and honeysuckle) were selected as raw materials for pyrolysis at different temperatures. The biochar obtained was used as a carrier to immobilize the highly efficient chlortetracycline-degrading bacterium Bacillus cereus LZ01 and analyze the complex’s removal characteristics and removal mechanism chlortetracycline. The results showed that the Chinese medicine residue biochar pyrolyzed at 500 °C had a higher removal capacity for chlortetracycline and could adsorb more microorganisms. The erding medicine residue biochar (EBC-500) pyrolyzed at 500 °C possessed a more developed pore structure and suitable nutrients. And the alkalinity of EBC-500 had the effect of relieving the inhibition of bacteria by acid, providing more suitable living conditions for the growth of bacteria, and improving the removal of chlortetracycline. Orthogonal experiments determined the optimal conditions for microbial immobilization by biochar: 10% microbial inoculum, 0.5 g biochar dosage, 0.097 - 0.15 mm biochar particle size, and 36 h immobilization time. The FT-IR spectra showed that the complex integrated all functional groups of biochar and degrading bacteria. The comparison of the removal effect before and after inactivation revealed that the removal mechanism of chlortetracycline in water by the complex was mainly determined by a combination of microbial degradation and biochar surface adsorption. This study provides a method for preparing an efficient biochar–microbial complex using Chinese medicine residue waste substrate, which provides a new idea for removing chlortetracycline from water.

High-pressure processing is a nonthermal method of food processing that is widely used in sterilization and enzyme inactivation. Although some works on technological parameters and quality evaluation have been performed, the mechanism of high pressure on food is still unclear. Due to the complexity of food ingredients, a tremendously important tripeptide in food proteins, orthorhombic l-glutathione, was employed in this work. In addition, in situ methods such as high-pressure Raman, infrared, and X-ray diffraction were used to investigate the structural changes in the pressure range of 0-10 GPa. Experimental results showed that the sample underwent two phase transitions in pressure intervals of 1.8-2.2 and 4.1-5.3 GPa. In addition, the strength of the hydrogen bonds (NH⋯O; OH⋯O; SH⋯O; CH⋯O) also changed in the two pressure intervals. This work may have potential research value for revealing the mechanism of high-pressure processing on food proteins.

The determination of energy consumption and conservation targets during the 13th Five-Year Plan lies in the core of the 13th Five-Year energy conservation planning. In this paper, the top-down decomposition methods was been employed to calculate China energy consumption, and research on the prediction of the development of industrial energy efficiency. In the end, author gave the suggestions to show the double control for energy consumption intensity and total consumption is the best way to fulfil the target of industrial energy efficiency of 13th five year plan energy consumption plan.

The goal of this study was to determine the factors that determine the degree of VR sickness in order to improve the audiovisual experience of VR videos or games. We used a simulator sickness questionnaire to evaluate the degree of VR sickness for nine types of live-action 180-degree videos, with a combination of different movement speeds and fields of view (FOV). Among the 40 participants we tested, those suffering from motion sickness had more serious symptoms than those without motion sickness. Although statistical tests failed to show significant differences related to the movement speeds or fields of view, our results suggested that VR exposure time was the most important factor influencing VR sickness.

The aerosol scattering properties of submicron (PM1) and sub-10 μm particles (PM10) under dry conditions (RH

To explore the properties of D-fructose under high pressure, we apply Raman, mid-infrared spectroscopy and X-ray diffraction to study the structure changes of D-fructose crystals. It has been revealed that D-fructose crystals underwent structural rearrangement at around 4.2–4.6 GPa, involving the generation of C–H⋯O hydrogen bonds and reducing the role of O–H⋯O hydrogen bonds. High-pressure Raman spectra indicated that the structure changed greatly at around 4.6 GPa, associated with the modification of bending vibrations of CH2 units and the disappearance of stretching vibrations of CH groups. In high-pressure mid-infrared experiments, the transition occured at around 4.2 GPa, with the changes of internal modes and disappearance of stretching vibrations of CH groups. Our X-ray diffraction experiments showed that the crystal lattice of D-fructose has been obviously modified under high pressure. All the diffraction peaks shift towards higher two-theta angles, which is due to the reduced interplanar distances as well as decrement of unit cell volume under high pressure. Furthermore, the structure rearrangement of D-fructose under high pressure is reversible. For the first time, the structure of D-fructose crystals was dynamically analyzed under high pressure, and we proposed the possible hydrogen bond changes, which is closely related to the sweetness and other properties of fructose.

Hydrogen energy is becoming more and more blooming because of its diversified sources, eco-friendly and green, easy storage and transportation, high-efficient utilization, etc. The use of hydrogen as an energy carrier is expected to grow over the next decades. Hydrogen, like electricity, is a secondary energy. Hydrogen production is the foundation for all kinds of applications. Based on the resources situation in China, potential of hydrogen production is analysed. China has a large potential of hydrogen production from coal, which is about 2.438 billion tons. Potential of hydrogen production from natural gas is less than that from coal, which is about 501 million tons. According to the average consumption of methanol per year, potential of hydrogen production from methanol is about 690, 000 tons per year. Potential of hydrogen production from industrial gas (coking, petrochemical and chlor-alkali industries) is about 866, 400 tons per year. Potential of hydrogen production from abandoned renewable energy power is about 1798.2 million tons per year. Distribution of resources in China differs among provinces. The deployment of hydrogen industry should pay attention to local hydrogen production potential. A green hydrogen production method, such as water electrolysis by renewable energy power, is a promising and environmental friendly way.

The paper examines the requirements of domestic policies and plans for water reuse standardization work, analyzes the current status and existing problems of domestic water reuse standards, builds China’s water reuse standard system and conducts an in-depth study on the structure and composition of the standard system.