Radiative forcing of organic aerosol in the atmosphere and on snow: Effects of SOA and brown carbon

Organic aerosols (OA) play an important role in climate change. However, very few calculations of global OA radiative forcing include secondary organic aerosol (SOA) or the light‐absorbing part of OA (brown carbon). Here we use a global model to assess the radiative forcing associated with the change in primary organic aerosol (POA) and SOA between present‐day and preindustrial conditions in both the atmosphere and the land snow/sea ice. Anthropogenic emissions are shown to substantially influence the SOA formation rate, causing it to increase by 29 Tg/yr (93%) since preindustrial times. We examine the effects of varying the refractive indices, size distributions for POA and SOA, and brown carbon fraction in SOA. The increase of SOA exerts a direct forcing ranging from −0.12 to −0.31 W m −2 and a first indirect forcing in warm‐phase clouds ranging from −0.22 to −0.29 W m −2 , with the range due to different assumed SOA size distributions and refractive indices. The increase of POA since preindustrial times causes a direct forcing varying from −0.06 to −0.11 W m −2 , when strongly and weakly absorbing refractive indices for brown carbon are used. The change in the total OA exerts a direct forcing ranging from −0.14 to −0.40 W m −2 . The atmospheric absorption from brown carbon ranges from +0.22 to +0.57 W m −2 , which corresponds to 27%~70% of the black carbon (BC) absorption predicted in the model. The radiative forcing of OA deposited in land snow and sea ice ranges from +0.0011 to +0.0031 W m −2 or as large as 24% of the forcing caused by BC in snow and ice simulated by the model. Key Points A fully explicit SOA formation model is used to determine SOA radiative forcing The direct radiative forcing by brown carbon in SOA is estimated The radiative forcing of OA in snow/ice is estimated for the first timePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108060/1/jgrd51450.pd

Key technologies research on of soil-structure interaction base story isolated structure response in 3D seismic zone

The development of karst in Karst area leads to poor stability of stratum. If earthquake occurs, the area will produce destructive disaster. In order to improve the stability capacity of the grassroots in the region, this study investigates the seismic response of inter-story isolation structures considering soil-structure interaction (SSI) in three-dimensional earthquakes. A model of the inter-story isolation structure incorporating SSI was developed, and one-dimensional, two-dimensional, and three-dimensional ground motions were applied to compare the seismic response under different input conditions. A three-dimensional isolation system was introduced and compared with traditional horizontal isolation structures to address excessive tensile and compressive stresses on the isolation structure during three-dimensional ground motion. The results demonstrate that the seismic response to three-dimensional earthquakes surpasses one-dimensional and two-dimensional inputs. Furthermore, adding a three-dimensional isolation structure effectively isolates vertical ground motion and reduces structural seismic response. Moreover, it minimizes soil stresses on the foundation compared to traditional horizontal isolation structure, enhancing foundation stability. This study will provide theoretical value and practical guidance for the research on key technology of SSI base story isolation structure response in Karst Plateau 3D Seismic zone

Prevalence of low back pain and associated occupational factors among Chinese coal miners

<p>Abstract</p> <p>Background</p> <p>Very few studies have evaluated the association between occupational factors and low back pain (LBP) among miners. The epidemiological data on LBP in Chinese miners are limited. The aim of this study was to measure the prevalence of low back pain in Chinese coal miners and to investigate the role of occupational factors.</p> <p>Methods</p> <p>A cross-sectional survey was conducted to examine 1573 coal miners in northern China. The prevalence of LBP over a 12-month period was assessed using the Nordic Musculoskeletal Questionnaire. Odds ratios were calculated to examine the association between the prevalence of LBP over a 12-month period and occupational factors using logistic regression.</p> <p>Results</p> <p>Among the coal miners, 64.9% self-reported LBP in a 12-month period. Occupational factors associated with LBP were identified, including tasks with a high degree of repetitiveness (OR 1.3, 95%CI 1.0-1.6), tasks characterized by a high level of physical demand (OR 1.4, 95% CI 1.1-1.8), posture requiring extreme bending (OR 1.6, 95% CI 1.2-1.7) and insufficient recovery time (OR 1.4, 95% CI 1.0-1.8).</p> <p>Conclusion</p> <p>Low back pain is common among Chinese miners. There were strong associations with occupational factors.</p

The ALMA-QUARKS Survey: II. the ACA 1.3 mm continuum source catalog and the assembly of dense gas in massive star-forming clumps

Leveraging the high resolution, high sensitivity, and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array (ALMA), the QUARKS survey, standing for "Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures", is observing 139 massive star-forming clumps at ALMA Band 6 ($\lambda\sim$ 1.3 mm). This paper introduces the Atacama Compact Array (ACA) 7-m data. Combining multi-wavelength data, we provide the first edition of QUARKS atlas, offering insights into the multiscale and multiphase interstellar medium in high-mass star formation. The ACA 1.3 mm catalog includes 207 continuum sources that are called ACA sources. Their gas kinetic temperatures are estimated using three formaldehyde (H$_2$CO) transitions with a non-LTE radiation transfer model, and the mass and density are derived from a dust emission model. The ACA sources are massive (16-84 percentile values of 6-160 $M_{\odot}$), gravity-dominated ($M\propto R^{1.1}$) fragments within massive clumps, with supersonic turbulence ($\mathcal{M}>1$) and embedded star-forming protoclusters. We find a linear correlation between the masses of the fragments and the massive clumps, with a ratio of 6% between the two. When considering the fragments as representative of dense gas, the ratio indicates a dense gas fraction (DGF) of 6%, although with a wide scatter ranging from 1% to 10%. If we consider the QUARKS massive clumps to be what is observed at various scales, then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster formation. With the ACA data over four orders of magnitude of luminosity-to-mass ratio ($L/M$), we find that the DGF increases significantly with $L/M$, which indicates clump evolutionary stage. We observed a limited fragmentation at the subclump scale, which can be explained by dynamic global collapse process.Comment: 24 pages, 7 figures. Accepted for publication in Research in Astronomy and Astrophysics. QUARKS atlas link: https://drive.google.com/file/d/1KTqXxCDduYepvLd9kIvZVSSytK48OmfL/view?usp=sharin

A comparison of the gender-specificity of age of consent legislation in Europe and China: Towards a gender-neutral age of consent in China?

Age of consent—the age at which young people are considered legally competent to consent to sexual activities—is an important weapon invented by law makers to protect young children from being sexually abused and exploited by predatory adults. In this study, a comparison of the age of consent legislation in 2004 and 2016 in Europe reveals that it is a trend for European law makers to adopt a gender-neutral approach in their age of consent legislation, i.e., the gender of the sexual participants does not affect the legal consequence of the sexual activity and both male and female children, either in heterosexual or homosexual relations, enjoy protection to the same extent. Then the age of consent legislation in China is deeply examined to see whether it is gender-neutral as most of the European jurisdictions. Based on the previous introduction and analysis of Europe and China, this paper concludes that the gender-neutral trend identified in Europe could be instructive for China’s future age of consent legislation

Present Status and Prospect of Ultra High Strength Steel Applied to Aircraft Landing Gear

The paper presents the domestic and overseas current status of the steel applied to aircraft landing gear in combination of the design concept and requirements for aircraft landing gear. The application features and concept of the steel used for landing gear are summarized and the domestic and overseas status are compared. For the moment, the low-alloy ultra-high strength steel and high-alloy ultra-high strength steel are all being used in the material system for aircraft landing gear steel, and the complete technical system for its anti-fatigue manufacturing is built. At present, China's development and application of high strength steel applied to aircraft landing gear is at the world advanced level. At last, the prospect for future development is analyzed

Operational Strategy for Low-Carbon Supply Chain under Asymmetric Information of Fairness Concerns

Carbon emission reduction has become a common hot topic around the world. Although the previous literature has proven that the asymmetric information and fairness concerns would influence the operational strategy for low-carbon supply chain, it hardly touched the asymmetric information of fairness concerns, which contradicted practical observations and experimental evidence. Incorporating the asymmetric information of fairness concerns, this paper investigates a low-carbon supply chain consisting of a manufacturer and a retailer with discrete types including selfish S-type and fairness-concerned F-type. The manufacturer can observe and thereby know the behavioral type of the retailer in the scenario of symmetric information, while it cannot in the scenario of asymmetric information. In the approach of game theory, the optimal carbon emission reducing strategy and pricing strategy in the symmetric scenario and asymmetric scenario are achieved successively. By comparing the above two scenarios, the impacts stemming from the asymmetric information of fairness concerns at the individual level and systematic level are analyzed, respectively. A case study is offered before concluding some implications for the supply chain management. The findings include the following: Firstly, the asymmetric information of fairness concerns enhances the carbon emission reduction significantly. Although the fairness concerns alone decrease the carbon emission reduction, the asymmetric information increases with the dominating power. Secondly, the asymmetric information of fairness concerns raises the wholesale price and retail price dramatically. Although the impact of either fairness concerns or asymmetric information randomly changes with the behavioral type and information structure, their interactive impacts are stable and change smoothly. Thirdly, the asymmetric information of fairness concerns promotes a fairer profit distribution, while either fairness concerns or asymmetric information alone hardly changes the overall profit of the low-carbon supply chain

Assessment of Future Water Yield and Water Purification Services in Data Scarce Region of Northwest China

Water shortage and pollution have become prominent in the arid regions of northwest China, seriously affecting human survival and sustainable development. The Bosten Lake basin has been considered as an example of an arid region in northwest China, and the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model has been used to quantitatively evaluate the future water yield and water purification services for four representative concentration pathways (RCP) scenarios. The results show that for the four RCP scenarios, the annual average precipitation in 2020–2050 decreases compared to that in 1985–2015; the area of cultivated land and unused land decreases, and the area of other land-use types increases from 2015 to 2050. The water yield service reduces, while the water purification service increases from 2015 to 2050 in the Bosten Lake basin. In 2050, the water yield and water purification services are the best for the RCP6.0 scenario, and are the worse for the RCP4.5 scenario and RCP8.5 scenario, respectively. The distribution of the water yield and water purification services show a gradual decline from northwest to southeast