China-US Relations in the 1940s - Early 2020s: Establishment and Key Challenges

The relevance of the research subject is conditioned upon the deterioration of diplomatic ties between the United States of America and the People's Republic of China. Clarifying this issue is, in addition, crucial considering the current unstable geopolitical situation. The purpose of the study was to identify the main stages of development of economic, political and social relations between the two countries and the problematic issues faced by the respective states. Methods used in the study: historical method, statistical method, systemic method, method of analysis and synthesis, comparative method etc. The chronology of China-US diplomatic relations was clarified, and the historical events that accompanied the development of the relevant relations were considered. The author examines the impact of these relations on the state of China-US ties, including the impact of World War II, the communist regime in the People's Republic of China, etc. In addition, the study includes statistics related to the so-called “trade war” between China and the United States. The main aspects of the Taiwan issue and the position of both the US and Chinese sides on this territory are clarified. In addition, attention was paid to the US and China's response to the Ukrainian-russian war, etc. The results of the research can be used by sociologists, lawyers and historians to write essays and dissertations. The data obtained can serve as a foundation for improving and enhancing diplomatic relations between the countries examine

Experimental Research and Theoretical Analysis on Throttling Characteristics of Electronic Expansion Valve in Series with Capillary Tube

The mass flow rate of R-32 and volumetric flow rate of dry air in an electronic expansion valves(EEV) , in two different capillary tubes(CT) and in one expansion valve in series with two different capillary tubes were tested, and the theoretical volumetric flow rate of dry air in one EEV in series with different CTs were predicted through a theoretical throttling model built in this paper. The results showed that the mass flow rate of R-32 or volumetric flow rate of dry air of the serial throttling component was lower than but close to that of the EEV in low openings and that of the CT in full opening, respectively, under the same operating conditions. The flow rate ratio of the serial throttling component to the EEV decreased fast with opening increasing, and the flow rate ratio of the refrigerant was obviously lower than that of the dry air. The refrigerant mass flow rate of EEV in series with CT up flow was higher than that of the same EEV in series with the same CT down flow

Shear strength of cemented sand gravel and rock materials

Shear strength is currently a significant parameter in the design of cemented sand gravel and rock (CSGR) dams. Shear strength tests were carried out to compare material without layers noumenon and layer condition. The experimental results showed good linearity in the curves of shear strength and pure grinding tests with correlation coefficients of nearly 97%. The friction coefficient was similar to that of C10 roller-compacted concrete (RCC), but the cohesion value was weaker than that of RCC. The shear strength of the CSGR layers decreased by 40% when retarding mixtures were not added and the layer was paved immediately after 4 h of waiting interval

Effect of tumor and normal lung volumes on the lung volume–dose parameters of IMRT in non–small-cell lung cancer

OBJECTIVES: To explore the effect of tumor and normal lung volumes on lung volume-dose parameters in patients with non-small-cell lung cancer (NSCLC) who had undergone intensity-modulated radiation therapy (IMRT). METHODS: The clinical data of 208 patients with NSCLC who underwent radical IMRT between June 2014 and June 2018 were retrospectively analyzed. A regression model curve was used to evaluate the effect of tumor and normal lung volumes on normal lung relative volumes receiving greater than 5 and 20 Gy (V5, V20), on mean lung dose (MLD), and on absolute volumes spared from greater than 5 and 20 Gy (AVS5, AVS20). RESULTS: The V5, V20, and MLD of the bilateral lung were fitted to a quadratic equation curve with the change in tumor volume, which increased initially and then decreased when the tumor volume increased. The V5, V20, and MLD of the lung reached their apex when the tumor volumes were 288.07, 341.69, and 326.83 cm3, respectively. AVS5 and AVS20 decreased in a logarithmic curve with an increase in tumor volume. The V5, V20, and MLD of the small normal lung volume group were all significantly higher than those of the large normal lung volume group (p<0.001, p=0.004, p=0.002). However, the AVS5 and AVS20 of the small normal lung volume group were all significantly lower than those of the large normal lung volume group (p<0.001). CONCLUSION: The effects of tumor volume and normal lung volume on dose-volume parameters should be considered. AVS5 is an important supplementary dose limitation parameter for patients whose tumor volume exceeds a certain boundary value (approximately 300 cm3)

Spin-glass ground state in a triangular-lattice compound YbZnGaO4_4

We report on comprehensive results identifying the ground state of a triangular-lattice structured YbZnGaO$_4$ to be spin glass, including no long-range magnetic order, prominent broad excitation continua, and absence of magnetic thermal conductivity. More crucially, from the ultralow-temperature a.c. susceptibility measurements, we unambiguously observe frequency-dependent peaks around 0.1 K, indicating the spin-glass ground state. We suggest this conclusion to hold also for its sister compound YbMgGaO$_4$, which is confirmed by the observation of spin freezing at low temperatures. We consider disorder and frustration to be the main driving force for the spin-glass phase.Comment: Version as accepted to PR

A facile and general approach for the synthesis of fluorescent silica nanoparticles doped with inert dyes

A general and facile approach was developed for the synthesis of almost monodisperse fluorescent silica nanoparticles (NPs) doped with inert dyes, which are organic fluorophores that are strongly fluorescent but are hydrophobic or lack a covalent binding group. The prepared NPs were mesoporous and the dye molecules were encapsulated in the pores via hydrophobic interaction with the CTAB template. The NPs were stable and highly fluorescent in aqueous solution, and have potential applications in bioanalysis and fluorescence encoding.National Natural Science Foundation of China[20875079, 20835005]; Planned Science and Technology Project of Xiamen, China[3502z20080011]; Specialized Research Fund for the Doctoral Program of Higher Education of China[200803840007

Molecule-scale controlled-release system based on light-responsive silica nanoparticles

We report a molecule-scale controlled-release system based on silica nanoparticles bearing a photoactive o-nitrobenzyl bromide linkage, which allows cage and release of drug or biologically active molecules by light