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The effective and efficient refractive index of a multilayer optical waveguide is computed by taking into account the various order modes of the waveguide, such as the Quasi-Transverse Electric/Transverse Magnetic (Quasi-TE/TM) mode. According to the effective refractive index method, the effective refractive index of the Quasi-TE/TM mode is calculated from the electromagnetic field curve distribution calculated for each mode in the 6-layer loss optical waveguide compute the effective refractive index each order of TE/TM mdes. Further, we analyze the dependence of the waveguide properties on the structure. We conclude that the mode effective refractive index and mode order do not decrease monotonicallythe lossy waveguide mode is more prevalent. The research work in this paper can be used as the theoretical basis for the design, fabrication and application of practical optical waveguide devices.

GH4720Li superalloy has been widely employed in high-performance aero engines turbine disks and other rotating component due to the excellent high temperature strength, anti-fatigue, corrosion resistance and long-term structural stability. The mechanism of function and evolution rule of γ'phase in GH4720Li superalloy was summed up in this paper. The relationship between γ'phase and high-temperature properties and the interaction law of γ'phase and residual stress were analyzed. In addition, the research progress of the new superalloy which was designed on the basis of GH4720Li superalloy was summarized, the future application of partitioned cooling technology and dual-organization dual-performance disk preparation technology was prospected.

Objective To investigate the expression of cannabinoid type 2 receptor （CB2R） at different time points after brain contusion and its relationship with wound age of mice. Methods A mouse brain contusion model was established with PCI3000 Precision Cortical Impactor. Expression changes of CB2R around the injured area were detected with immunohistochemical staining, immunofluorescent staining and Western blotting at different time points. Results Immunohistochemical staining results showed that only a few cells in the cerebral cortex of the sham operated group had CB2R positive expression. The ratio of CB2R positive cells gradually increased after injury and reached the peak twice at 12 h and 7 d post-injury, followed by a decrease to the normal level 28 d post-injury. The results of Western blotting were consistent with the immunohistochemical staining results. Immunofluorescent staining demonstrated that the changes of the ratio of CB2R positive cells in neurons, CB2R positive cells in monocytes and CB2R positive cells in astrocytes to the total cell number showed a single peak pattern, which peaked at 12 h, 1 d and 7 d post-injury, respectively. Conclusion The expression of CB2R after brain contusion in neurons, monocytes and astrocytes in mice suggests that it is likely to be involved in the regulation of the biological functions of those cells. The changes in CB2R are time-dependent, which suggests its potential applicability as a biological indicator for wound age estimation of brain contusion in forensic practice.

X-ray Fluorescence Spectrometry (XRF) can be used to rapidly determine the total content of barium in barite. However, the barium carbonate included in the total barium will result in inaccurate results of barium sulfate. Moreover, copper, lead, zinc and other non-ferrous metal elements can damage the sample melting pot. Acid treatment is required to remove interference such as barium carbonate and lead. The residue ratio of the different samples after the acid treatment is different to before and the ratio of the flux to sample is uncertain, and thus the content of barium sulfate cannot be accurately determined. Therefore, it is essential to ensure that the melting agent has the same proportion as the sample. The sample pretreatment conditions, melting conditions and equipment conditions were optimized and are described in this paper. 10% hydrochloric acid mixed with 10% nitric acid was used to dissolve the sample. The sample solution was filtered to remove barium carbonate, calcium sulfate and copper, lead, zinc and other non-ferrous metal elements. Alumina oxide was added to undissolved samples after 700℃ calcination to reach the original sample weight, which attains the same proportion of flux and sample. Ammonium nitrate was used as the oxidant, and lithium bromide and ammonium iodide were used as demoulding agents. Samples were melted at 1075℃, and barium sulfate content in the barite was determined by XRF. The relative standard deviation (RSD) of the method is less than 0.4% and the detection limit is 72 μg/g. This method needs less detection time and suffers from less interference elements than determination by Inductively Coupled Plasma-Optical Emission Spectrometry, improving the test efficiency and analysis quality.

Bromine exists mainly as ions in bromide brine and halide sulfate brine in the hydrosphere of the crust. Powder carrier pellet method is commonly used in analyzing bromine in brine by Wavelength Dispersive X-ray Fluorescence Spectrometry (WDXRF). However, this sample preparation method has the disadvantages of large work load, sample inhomogeneity and outer contamination, which affects the analytical accuracy. Samples were pretreated by film adsorption, and film material and sample weight were optimized and are reported in this paper. Firstly, 50 μL of brine is dropped to the center of a chromatography filter paper (Ф=40 mm), air dried, and then flattened by high pressure to prepare the film sample for WDXRF test. A standard curve of Br was calibrated by self-prepared standard solution. Experimental results show that the impact of coexisting ions such as K+, Na+, Ca2+, Mg2+, Cl- and SO42- on the detection of Br is negligible. The detection limit of this method is 0.95 mg/L, the precision is less than 0.8% (n=11), and the recoveries are 99.4%-101.2%. The new sample preparation method is very economical and easy to operate, avoiding the use of chemical reagent.

The method of carbon-loaded foam plastic adsorption has good adsorption properties of gold, but is only suitable for filtration adsorption with complicated analytical procedures. Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) with carbon-loaded foam plastic adsorption was used to determine the content of gold in gold ore and is described in this paper. The gold ore sample was firstly burned at 650℃ for 2 h, followed by dissolution with 50% aqua regia and 10% ferric chloride, then oxidated with 5% potassium permanganate. Gold in the solution was adsorbed twice by carbon-loaded foam plastic. The carbon-loaded foam plastic with gold was burned at 580℃ and dissolved in 50% aqua regia, after which the content of gold could be measured by ICP-OES. The detection limit is 0.002 μg/g and precision (RSD, n=11) is less than 3.7%. The method of gold adsorption rate is greater than 99.9% and the measured range is 0.01-90 μg/g. The method has a strong adaptability to different types of gold ore with higher accuracy for low content and high content of the samples than the previous method.

The proportion of the car is one of the important parts of car styling design. The study of the car proportion is of great significance. The proportion of the car is determined by the technical conditions, functions and aesthetics. At present, there're not many studies on the area proportion of the car .There're studies on the line relationship and length, width, height proportion of the car. This paper uses computer image processing method to calculate the projected area proportion of the hatchback car. And it provides a new thinking and method for the car proportion study. The result shows that the projected area proportion values of the hatchback cars of European, American, Japanese, Korean and Chinese series on the market have a difference, but are close. And the total average projected area proportion values of car window and car body of the hatchbacks have been calculated.

W ith the fast growth of human population, socio-economic development and resource exploitation, significant alterations have unfolded within the Poyang Lake ecosystem, thrusting environmental concerns to the forefront. Presently, total Phosphorus levels in the Poyang Lake region surpass established standards, and this concentration continues to surge, bearing witness to the progressive deterioration of the lacustrine biosphere. Designated as a priority demonstration area for national ecological civilization construction and Yangtze River protection and restoration, phosphorus pollution in the Poyang Lake Basin has emerged as a critical and urgent challenge in Jiangxi Province s management of its aquatic ecological environment. Based on the technological method of watershed zoning in the pollution source census, it presents the estimation of the total phosphorus pollution load and the quantitative analysis of phosphorus pollution sources entering the lake. The results show that the total phosphorus pollution load entering Poyang Lake in 2021 reached 14 900 tons, with the primary pollution originating from the land-based input, accounting for 87.73% of its contribution ; in order of contributing weight, the sources of pollution within the lake primarily arose from endogenous releases (5.52%) and soil erosion (4.60%). Our analysis ranks the pollution sources in descending order of contribution weight as follows: Livestock farming (48.63%) > Urban living (20.01%) > Cultivation (9.71%) > Aquaculture (7.37%) > Endogenous r elease (5.52%) > Soil erosion (4.6%) > Industrial enterprises (1.12%) > Rural domestic (0.89%) > Migratory bird droppings (0.46%) > Tourism (0.12%).Notably, livestock farming emerges as the primary contributor to agricultural surface contamination concerning the total phosphorus indicator. Regarding spatial distribution, high-contributing watersheds of total phosphorus load are primarily concentrated in the Ganjiang River Gathering Area and the Binhu Area, with the contribution proportion of 50.67% and 25.92%, respectively, and concentrated production of total phosphorus in the catchment areas of the Fu River and Xinjiang River, with a contribution of 7.64% and 8.34%, the remaining catchment areas generated load into the lake with relatively low intensity, accounting for contributions totaling 7.39%. Moreover, a similar contributing structure of pollution sources in each sub-region is mainly presented as agricultural sources as the main source, with urban sources as a secondary source. Based on the research findings, it is evidenced that the sources of total phosphorus pollution in Poyang Lake exhibit spatial variability. However, the principal control sources for total phosphorus in the lake show similarities across different regions. To effectively address these concerns and enhance the overall ecological well-being of the Poyang Lake Basin, this paper strongly recommends prioritizing the control of high-contributing watersheds, such as the Binhu District and the Ganjiang Watershed. Mitigating phosphorus pollution effectively would require tailored prevention and reduction strategies, especially focusing on agricultural and urban living. Initiatives such as relocating livestock farming to areas with large environmental capacity, emissions reduction measures, and eco-friendly enrichment. Implementing these measures holds the promise of alleviating the issue of total phosphorus pollution and ensuring the sustainable development of Poyang Lake and the stability of its hydro-ecosystem. [ABSTRACT FROM AUTHOR]