436 research outputs found
Study on the factors affecting the adsorption of CO2 from power plant flus gas in coal left in goaf area
Utilizing the adsorption characteristics of coal rock in the goaf to storage CO2 not only reduces the cost of carbon capture and separation, but also prevents spontaneous combustion of coal left in goaf area. The effects of pore structure, mineral content and moisture content on the CO2 adsorption characteristics of coal were investigated using adsorption experiments at ambient temperature and pressure, ASAP specific surface area and pore size analysis experiments. Then the quantitative relationship equations of factors affecting CO2 adsorption in coal were fitted, and the importance weights of each influence was calculated by Random Forest algorithm. The results shown that, the pore size distribution of three coals from the mining area of Dananhu (DNH), Hegang (HG) and Tongxin (TX) were basically the same. The number of pores in the range of 0.5-0.7 nm and 0.8-0.9 nm was more, and that in the range of 0.7-0.8 nm was less. The number of micropores was the fundamental reason for the difference in CO2 adsorption capacity of three coals. At ambient temperature and pressure, the saturated adsorption amount of CO2 in coal increased with the increasing specific surface area, and decreased with the increasing mineral content and moisture content. The more the number of micropores of coal, the more significant the influence of mineral content and moisture content on the adsorption amount. After the coal reached the critical moisture content, the saturated CO2 adsorption amount gradually tended to be stable because the water molecules hindered the flow channels of CO2 molecules, resulting in the CO2 molecules not being able to enter into the pores inside the coal. The specific surface area had the greatest influence on the adsorption amount, followed by the moisture content and pore volume, and the mineral content was the weakest. Specific surface area and moisture content had a combined importance weight of 75.1%, which was much higher than the other two factors. According to the fitting equation, the saturated adsorption amount of CO2 in coal can be inferred by determining the specific surface area, mineral content and moisture content of coal, which provide a theoretical basis for CO2 adsorption and storage by coal left in goaf area
1-Benzyl-1,4-diazepan-5-one
The title compound, C12H16N2O, is a diazepane intermediate that can be used as an inhibitor of human nitric oxide synthesis. In the molecule, the seven-membered ring has a chair-like conformation and the two rings are approximately perpendicular to one another, with a C—N—C—C torsion angle of 77.8 (4)°. Intermolecular N—H⋯O hydrogen bonds link the molecules into dimers around a centre of symmetry, with C—H⋯O interactions linking the dimers into infinite sheets
Superconductivity at 22.3 K in SrFe2-xIrxAs2
By substituting the Fe with the 5d-transition metal Ir in SrFe2As2, we have
successfully synthesized the superconductor SrFe2-xIrxAs2 with Tc = 22.3 K at x
= 0.5. X-ray diffraction indicates that the material has formed the
ThCr2Si2-type structure with a space group I4/mmm. The temperature dependence
of resistivity and dc magnetization both reveal sharp superconducting
transitions at around 22 K. An estimate on the diamagnetization signal reveals
a high Meissner shielding volume. Interestingly, the normal state resistivity
exhibits a roughly linear behavior up to 300 K. The superconducting transitions
at different magnetic fields were also measured yielding a slope of -dHc2/dT =
3.8 T/K near Tc. Using the Werthamer-Helfand-Hohenberg (WHH) formula, the upper
critical field at zero K is found to be about 58 T. Counting the possible
number of electrons doped into the system in SrFe2-xIrxAs2, we argue that the
superconductivity in the Ir-doped system is different from the Co-doped case,
which should add more ingredients to the underlying physics of the iron
pnictide superconductors.Comment: 4 pages, 4 figure
Genome-wide patterns of genetic variation in sweet and grain sorghum (Sorghum bicolor)
10.1186/gb-2011-12-11-r114Genome Biology1211-GNBL
Research Progress on Effect of Brewing Methods on Brewing Quality of Rice Paste
Instant rice paste is a kind of colloidal solution with certain viscosity and consistency formed by mechanical crushing and boiling of grain. Due to its functional characteristics of instant energy supply, strong flavor and rich nutrition, it can quickly adapt to today’s fast-paced life. Water temperature and water quantity can influce water solubility index and gelatinization degree of rice paste after gelatinization. Pasting viscosity and dissolved lubrication degree of rice paste can be affected by punching particle size and modifier treatment. Suitable bubbling parameters based on pasting properties and solubility of rice paste can effectively improve the instant solubility, stability and taste of rice paste. The effects of four brewing methods (water temperature, water volume, particle size and modifier treatment) on the rheology, texture and sensory quality of cereal paste were reviewed. It is expected to provide some reference for the practical application of rice paste
Solving Small Exponential ECDLP in EC-based Additively Homomorphic Encryption and Applications
Additively Homomorphic Encryption (AHE) has been widely used in various applications, such as federated learning, blockchain, and online auctions. Elliptic Curve (EC) based AHE has the advantages of efficient encryption, homomorphic addition, scalar multiplication algorithms, and short ciphertext length. However, EC-based AHE schemes require solving a small exponential Elliptic Curve Discrete Logarithm Problem (ECDLP) when running the decryption algorithm, i.e., recovering the plaintext from . Therefore, the decryption of EC-based AHE schemes is inefficient when the plaintext length . This leads to people being more inclined to use RSA-based AHE schemes rather than EC-based ones.
This paper proposes an efficient algorithm called for solving the small exponential ECDLP at -bit security level. We perform a series of deep optimizations from two points: computation and memory overhead. These optimizations ensure efficient decryption when the plaintext length is as long as possible in practice. Moreover, we also provide a concrete implementation and apply to some specific applications. Experimental results show that is far faster than the previous works. For example, the decryption can be done in ms with a single thread when , which is about times faster than that of Paillier. Furthermore, we experiment with from to , and the existing works generally only consider . The decryption only requires second with threads when . In the practical applications, we can speed up model training of existing vertical federated learning frameworks by to times. At the same time, the decryption efficiency is accelerated by about times in a blockchain financial system (ESORICS 2021) with the same memory overhead
Scientometric trends and knowledge maps of global health systems research
Background: In the last few decades, health systems research (HSR) has garnered much attention with a rapid increase in the related literature. This study aims to review and evaluate the global progress in HSR and assess the current quantitative trends. Methods: Based on data from the Web of Science database, scientometric methods and knowledge visualization techniques were applied to evaluate global scientific production and develop trends of HSR from 1900 to 2012. Results: HSR has increased rapidly over the past 20 years. Currently, there are 28,787 research articles published in 3,674 journals that are listed in 140 Web of Science subject categories. The research in this field has mainly focused on public, environmental and occupational health (6,178, 21.46%), health care sciences and services (5,840, 20.29%), and general and internal medicine (3,783, 13.14%). The top 10 journals had published 2,969 (10.31%) articles and received 5,229 local citations and 40,271 global citations. The top 20 authors together contributed 628 papers, which accounted for a 2.18% share in the cumulative worldwide publications. The most productive author was McKee, from the London School of Hygiene \& Tropical Medicine, with 48 articles. In addition, USA and American institutions ranked the first in health system research productivity, with high citation times, followed by the UK and Canada. Conclusions: HSR is an interdisciplinary area. Organization for Economic Co-operation and Development countries showed they are the leading nations in HSR. Meanwhile, American and Canadian institutions and the World Health Organization play a dominant role in the production, collaboration, and citation of high quality articles. Moreover, health policy and analysis research, health systems and sub-systems research, healthcare and services research, health, epidemiology and economics of communicable and non-communicable diseases, primary care research, health economics and health costs, and pharmacy of hospital have been identified as the mainstream topics in HSR fields. These findings will provide evidence of the current status and trends in HSR all over the world, as well as clues to the impact of this popular topic; thus, helping scientific researchers and policy makers understand the panorama of HSR and predict the dynamic directions of research
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