Carbon footprint and emission reduction potential of the artwork auction market

Greenhouse gas emissions from human activities have become the leading cause of climate problems. Reducing greenhouse gas emissions from human economic activities and realizing carbon neutralization are the main means of sustainable economic development. Among them, carbon emission reduction of large-scale activities including auctions bears the brunt. Through the emission factor method, this paper estimates the carbon footprint of a typical artwork auction and divides the auction market into different sizes, according to the average round-trip distance of the number of participants. The results show that a typical 3-day medium-sized artwork auction with 500 people’s carbon footprint is about 270 tons of carbon dioxide. The traffic carbon emission of participants accounts for a large proportion of the total carbon footprint, particularly composed of the traffic carbon emissions of a small proportion of long-distance participants. Therefore, the transition from offline to virtual artwork auctions can significantly reduce the carbon footprint by 90%–95%. We put forward suggestions on improving the auction carbon footprint accounting process and industry carbon neutralization system, and promoting the development of relevant technologies for the virtual artwork auction market

Search for light dark matter from atmosphere in PandaX-4T

We report a search for light dark matter produced through the cascading decay of $\eta$ mesons, which are created as a result of inelastic collisions between cosmic rays and Earth's atmosphere. We introduce a new and general framework, publicly accessible, designed to address boosted dark matter specifically, with which a full and dedicated simulation including both elastic and quasi-elastic processes of Earth attenuation effect on the dark matter particles arriving at the detector is performed. In the PandaX-4T commissioning data of 0.63 tonne$\cdot$year exposure, no significant excess over background is observed. The first constraints on the interaction between light dark matter generated in the atmosphere and nucleus through a light scalar mediator are obtained. The lowest excluded cross-section is set at $5.9 \times 10^{-37}{\rm cm^2}$ for dark matter mass of $0.1$ MeV$/c^2$ and mediator mass of 300 MeV$/c^2$. The lowest upper limit of $\eta$ to dark matter decay branching ratio is $1.6 \times 10^{-7}$

A Search for Light Fermionic Dark Matter Absorption on Electrons in PandaX-4T

We report a search on a sub-MeV fermionic dark matter absorbed by electrons with an outgoing active neutrino using the 0.63 tonne-year exposure collected by PandaX-4T liquid xenon experiment. No significant signals are observed over the expected background. The data are interpreted into limits to the effective couplings between such dark matter and electrons. For axial-vector or vector interactions, our sensitivity is competitive in comparison to existing astrophysical bounds on the decay of such dark matter into photon final states. In particular, we present the first direct detection limits for an axial-vector (vector) interaction which are the strongest in the mass range from 25 to 45 (35 to 50) keV/c$^2$

Development progress and outlook of deep and normal pressure shale gas of SINOPEC

In the past decade, with the improvement of shale gas exploration and development theory and techno-logy, the commercial development of marine shale gas from Ordovician Wufeng to Silurian Longmaxi formations in southern China has been achieved, and the target of shale gas exploration and development is gradually shifting towards shale gas of deep and complex structural areas and new formations. In order to further promote efficient exploration and development of shale gas, a systematic review was conducted on the recent exploration and deve-lopment progress of SINOPEC shale gas and an analysis was conducted on the development trend of shale gas in China. The research results indicate that: ① The high-quality Fuling National Shale Gas Demonstration Zone has been built and a key technology system for three-dimensional development of marine shale gas has been innovatively formed. ② The large-scale and efficient development of atmospheric shale gas in Dongsheng and Baima blocks of Nanchuan has been realized, and four shale gas accumulation and dispersion models have been constructed: anticline, monocline, reverse fault blocking, and residual syncline. A fine zoning and differentiated development model and a low-cost technology system for atmospheric shale gas have been preliminarily formed. ③ The deep large-scale fields of trillions of square meters in southeastern Sichuan basin edge have been preliminarily implemented, an "overpressure rich gas" model of marine deep shale gas has been innovatively formed, and a fracturing technology system of deep shale gas in the deep range of 4 000-4 500 m has been preliminarily formed. ④ Major breakthroughs have been made successively in Jurassic of Yuanba and Puguang, Permian of Hongxing and Puguang, and Cambrian of Jingyan and Qianwei. ⑤ The future breakthrough and development of shale gas cannot be achieved without innovative research on exploration and development theory and technology. The integration of exploration and development, geological engineering, and technology and economy must be adhered to. The complexity of deep, normal-pressured, and geological characteristics of new shale gas formations should be fully understood. In addition, policy support is also required

Determination of Double Beta Decay Half-Life of 136Xe with the PandaX-4T Natural Xenon Detector

Precise measurement of two-neutrino double beta decay (DBD) half-life is an important step for the searches of Majorana neutrinos with neutrinoless double beta decay. We report the measurement of DBD half-life of 136Xe using the PandaX-4T dual-phase Time Projection Chamber (TPC) with 3.7-tonne natural xenon and the first 94.9-day physics data release. The background model in the fiducial volume is well constrained in situ by events in the outer active region. With a 136Xe exposure of 15.5 kg-year, we establish the half-life as 2.27±0.03stat.±0.10syst.×1021 years. This is the first DBD half-life measurement with natural xenon and demonstrates the physics capability of a large-scale liquid xenon TPC in the field of rare event searches

Measurement of Double Beta Decay Half-life of 136^{136}Xe with the PandaX-4T Detector

Precise measurement of two-neutrino double beta decay~(DBD) half-life is an important step for the searches of Majorana neutrinos with neutrinoless double-beta decay. We report the measurement of DBD half-life of $^{136}$Xe using the PandaX-4T dual-phase Time Projection Chamber~(TPC) with 3.7-tonne natural xenon and the first 94.9-day physics data release. The background model in the fiducial volume is well constrained in situ by events in the outer active region. With a $^{136}$Xe exposure of 15.5\,kg-year, we establish the half-life as $2.27 \pm 0.03 (\textrm{stat.})\pm 0.09 (\textrm{syst.})\times 10^{21}$ year. This is the first DBD half-life measurement with natural xenon and demonstrates the physics capability of a large-scale liquid xenon TPC in the field of rare event searches.Comment: 6 pages, 4 figure