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The utilization of biofilters provides a promising option, serving as an environment-friendly and economically beneficial strategy for waste gas abatement. In this study, the different moisture content of vermicompost with indigenous microorganisms as a filter bed material was evaluated for the performance of a biofilter in terms of hydrogen sulfide removal efficiencies and the bacterial dynamics. Maximum removal efficiency of hydrogen sulfide was conformed when the moisture content of the packing material was from 50% to 60%. By 16S rDNA gene-Illumina Miseq high-throughput sequencing technology, The Shannon and Simpon index of the vermicompost microbial community had significantly decreased after treating hydrogen sulfide. The predominant bacteria in vermicompost samples were Proteobacteria, Gemmatimonadetes, Bacteroidetes and Actinobacteria. Rhodanobacter and Mesorhizobium were isogenous with sulfur-oxidizing bacteria, which play a critical role in vermicompost biodegrading hydrogen sulfide.

China is one of the countries with serious land degradation problems in the world. Land degradation directly threatens the food security of our country and determines the sustainable development of social economy. In this paper, the potential evapotranspiration and moisture index are calculated to divide the climatic zone of China. Based on the NPP and precipitation data, the national rRUE is obtained by the edge function. With the climate "relative benchmark", the rules of threshold analysis is used to comprehensively evaluate the land degradation in China. The results show that: excellent land is concentrated in northeast China, western Xinjiang and eastern Qinghai-Tibet Plateau; mildly degraded land is widely and sporadically distributed in the eastern plain of China; moderately degraded land and severely degraded land are concentrated in western Inner Mongolia, southern Xinjiang and northern Qinghai-Xizang Plateau.

This paper discusses the effects of land degradation assessment based on the index of net primary productivity (NPP), rain use efficiency of vegetation (RUE) and relative rain use efficiency of vegetation(rRUE). The results show that the land degradation evaluation method based on the correlation coefficient of NPP with time and the annual average and annual maximum of rRUE can comprehensively reflect the status of land productivity. It plays a good role in indicating the effect of land degradation, and is more conducive to remote sensing quantitative evaluation and rapid monitoring of large-scale land degradation.

Daqing Oilfield is rich in low permeability reservoirs. In order to fully understand the development dynamics of ultra-low permeability reservoirs, this paper takes Daqing Oilfield as an example and studies the productivity dynamics of fractured horizontal Wells by numerical simulation method. The results show that the productivity of fractured horizontal Wells decreases exponentially with the decrease of formation permeability. The productivity of fractured horizontal well increases with fracture length and decreases with fracture spacing. With the increase of formation coefficient and reservoir thickness, the productivity increase of fractured horizontal Wells decreases. In the case of small well spacing, the smaller the formation coefficient and reservoir thickness, the higher the productivity of fractured horizontal Wells. Compared with conventional vertical Wells, fractured horizontal Wells have better production performance.

Statistical gene detection plays an important role in biostatistics and bioinformatics. So far, many gene loci associated with human complex disease have been found by statistical methods. However, it is difficult to find all the mutation genes that are associated with a certain disease. Researchers need to detect more associated genes aiming at a disease so that human will conquer the disease one day. In this paper, we considered a real and big data set and study the detection problem of genes associated with the PIK3C2B gene on lung disease. 168 significant genes associated with the PIK3C2B gene were detected at nominal significance level 0.001 by using statistical multiple testing method. The detected genes will provide some reference to further study the function of the PIK3C2B gene to lung disease for biologists and medical scientists.

COVID-19, the disease caused by SARS-CoV-2, emerged in December 2019 in Wuhan, China, when Chinese authorities confirmed several patients with fever, difficulty breathing, and invasive lesions on the lungs. The virus then spread quickly across the globe, and by May 17, there were a total of 18,151,717 cases worldwide. While some countries still have an exponentially increasing rate of new cases, China has stabilized the spread of the virus. In the review of COVID-19 in this paper, we used sources from Google Scholar, PubMed, Research Gate, etc. In addition, when investigating public policy data and the number of infections, we also used the statements and relevant data from the official websites of the governments of Dalian and Beijing. Our investigation is based on the summary and analysis of the above data to reach our conclusion. We investigated the basic characteristics of COVID-19, the corresponding Sinovac vaccine and mRNA vaccine, the first round of outbreaks in Wuhan, Beijing, and Dalian, and the warning role of COVID-19 in the future. We demonstrated that keeping social distance and isolating infected patients in time can effectively block the transmission of the virus. This paper exposes the necessary public health measures during the pandemic, providing experiences and lessons for a potential future pandemic.

Some integral type boundary value problems (BVPs) for second order differential equations (ODEs) with one-dimensional p-Laplacian on the whole line are discussed. Sufficient conditions to guarantee the existence of solutions are established. The emphasis is put on the one-dimensional p-Laplacian term [ρ(t)Φ(x'(t))]' involved with the nonnegative function ρ that may satisfy $\rho(0)=0$, and the differential equations are defined on the whole line.

At present, multiphase flow productivity calculation requires many parameters, and most of them only consider oil and gas two-phase flow, which is complicated and limited. Therefore, a reasonable productivity formula of condensate gas reservoir with producing water is needed. The three-zone model of condensate gas reservoirs is generally applied to the physical model for inferring productivity. On this basis, an improved model is established, which includes that different seepage characteristics are considered for different zones. Moreover, the effects of inclined angle and water production on gas wells are regarded as pseudo-skin factors and additional-skin factors. In addition, Zone I considers the effects of high-speed nonDarcy effect(HSND), starting pressure gradient, stress sensitivity, inclined angle and water production; Zone II is the same way excepting starting pressure gradient and stress sensitivity ; Zone III only considers the effects of inclined angle and water production. As a result, a productivity equation with multiple factors for condensate gas wells is established. Through analysing cases and influences in H gas reservoir X1 well, the HSND, starting pressure gradient, stress sensitivity and water production have a negative impact on gas well productivity, but the inclined angle is opposite. Founded that the starting pressure gradient impacts on productivity is less than the HSND because of the limited radius of Zone I; the impact of the HSND on productivity increases with the decreasing of bottom hole pressure; the impact of water production on gas well productivity is much higher. When the angle is over 60°, the effect of gas

In the preparation of gas production plan and the study of gas well proration we often judge the fluid carrying capacity of gas well by the critical fluid carrying rate of the gas well, and then adjust the production plan. At present, spherical droplet model and ellipsoidal droplet model are often used to calculate the fluid flow in gas Wells, but the spherical cap droplet model has not been concerned by relevant scholars. Therefore, we studied the application range of spherical cap droplet model, established relevant mechanical expressions, and finally obtained the formula for calculating the minimum critical liquid carrying rate of spherical cap droplet model. The results show that the spherical cap droplet model cannot be ignored in the conventional droplet model and has a wide range of applications. At the same time, the model is validated by combining with gas Wells of H gas reservoir, and the model has good applicability.

Horizontal Wells are often used to develop condensate gas reservoirs. When there is edge water in the gas reservoir, it will have a negative impact on the production of natural gas. Therefore, reasonable prediction of its water breakthrough time is of great significance for the efficient development of condensate gas reservoirs.At present, the prediction model of water breakthrough time in horizontal Wells of condensate gas reservoir is not perfect, and there are mainly problems such as incomplete consideration of retrograde condensate pollution and inaccurate determination of horizontal well seepage model. Based on the ellipsoidal horizontal well seepage model, considering the advance of edge water to the bottom of the well and condensate oil to formation, the advance of edge water is divided into two processes. The time when the first water molecule reaches the bottom of the well when the edge water tongue enters is deduced, that is, the time of edge water breakthrough in condensate gas reservoir.The calculation results show that the relative error of water breakthrough time considering retrograde condensate pollution is less than that without consideration, with a higher accuracy. The example error is less than 2%, which can be effectively applied to the development of edge water gas reservoir.

For a better guidance of production, a combination of drill stem testing (DST), regional statistical method and pseudo steady-state seepage theory model was used to analyze the productivity of N gas reservoir in light of the complex geological features of the low-permeability thick-layer. Firstly, the DST method was used to test the N gas reservoir. And then the binomial pseudo-pressure method, binomial pressure square method and exponential method were used to interpret the test data of DST of this formation. Finally, the binomial pseudo-pressure interpretation method was used and the results showed that only the productivity of H3b layer was successfully tested of the four. The H3a, H4b and H5a layers are ultra-low pore and permeability gas reservoirs and the productivity of these layers can’t be explained by the available data due to the short testing time and a non-stationary state of testing pressure and quantity, resulting in the failure of the test. The productivity of the main layers were estimated and forecasted by the regional statistical method and the theoretical model of pseudo steady-state seepage, taking the arithmetic average value of the regional statistical method and the theoretical formula as the final value of absolute open flow rates(AOF). The final calculation results are as follows: the AOF of main gas layers H3a, H3b, H4b and H5a in N gas field is 31.30×104m3/d, 388.92×104m3/d, 20.82×104m3/d and 30.80×104m3/d, respectively. This method may sheds light on verifying and calculating the productivity of gas wells and determining the reasonable production allocation of gas wells.

In order to improve the seismic performance of common concrete shear wall with concealed bracings, fiber reinforced polymer modified concrete instead of ordinary concrete was applied to the shear wall as described in this paper. In this paper, the experimental study on the seismic performance of two different types of shear walls under cyclic loading was carried out, and also the failure characteristics, bearing capacity, ductility, hysteretic curve, stiffness attenuation and energy dissipation performance of the proposed shear wall were analyzed systematically. The test results show that the seismic performance of fiber-reinforced polymer modified concrete shear wall is significantly improved because its the damping ratio, deformation capacity and energy dissipation capacity are greatly improved compared with ordinary concrete shear wall with concealed bracings, which ensures its better stiffness stability in the later stage.