bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Experimental Construction of a Novel Brine-based Drilling Fluid for Salt-Anhydrite Formation
Authors: Lin Feng , Chang Congbing , Xu Lin , Wang Shengxiang
Published: November 2019

The salt-anhydrite formation has a highly negative impact on well construction, which can cause various drilling accidents upon drilling. In combination to salt-anhydrite characteristics of Missan Oilfields, a novel type of brine-based frilling fluid was established. The weighting manner of fixed salinity was evaluated, and key additives, viscosifier and filtrate reducer, were determined by single-factor experiments. The formula of brine-based drilling fluid was constructed as: fresh water + 0.6wt.% VIS + 2wt.% S-FLO+ (25wt.% NaCl + 5wt.% KCl + 8wt.% HCOONa) fixed salinity, which will be essential for further developing multifunctional high-density drilling fluids.
Laboratory optimization on performance of high density brine-based drilling fluid
Authors: Wang Shengxiang , Xu Lin , Yang peilong
Published: November 2019

The brine-based drilling fluid is paramount for drilling operation in the salt-anhydrite formations. In this work, a novel high density brine-based drilling fluid was designed and established, based on the features of salt-anhydrite formation in Missan Oilfields. A suite of laboratory tests has been carried out to comparatively evaluate effect of key additive amounts on standard properties of drilling fluids. The formula of the high density brine-based drilling fluid was optimized. The newly developed brine-based drilling fluid possesses excellent rheology, filtrate, thermal stabilization, inhibition and lubricity properties, which can provide an alternative to drilling through the salt-anhydrite formation in Missan Oilfields.
Detection and Analysis of the Concentration of Radioactive Radon in the Construction Environment of a University
Authors: Chen Shuyi , Gong Jinghui , Wan Letao , Chen Jingxian , Dong Yuan , Yuan Yuan
Published: November 2019

Radioactive radon is an important hazard in indoor air environments. In order to study the concentration of radon in the building environment, this paper tests the content of cockroaches in a university dormitory, teaching building and auxiliary room through experiments. And the experimental results are analyzed. The results show that: In the built environment, the closer the soil is to the foundation, the higher the concentration of radioactive radon, and the effect of temperature and humidity on the concentration of radioactive radon is very small.
Research progress in polymerization methods of emulsion acrylic acid pressure sensitive adhesive
Authors: Zhang Hongyan , Wang Huiqin , Wang Haiquan
Published: November 2019

In this paper, the characteristics of pressure-sensitive adhesive, the properties of pressure-sensitive adhesive and the preparation of pressure-sensitive adhesive are introduced. The research progress of emulsion acrylic pressure-sensitive adhesive is the focus of this paper. The methods of producing this kind of pressure-sensitive adhesive and their advantages and disadvantages in recent years are summarized.
Establishment of Clean Energy Demand Forecasting Model in China Based on Genetic Algorithms
Authors: Chen Jiying , Cheng Gaoyuan , Chi Shuanghe
Published: November 2019

In the future, energy development will face a series of severe challenges, such as insufficient domestic conventional energy resources, huge oil supply gap, large amount of clean energy needed by cities, and huge international pressure on global climate change. This paper uses historical data and genetic algorithm to improve it, and uses function expansion model to reveal the internal proportional connection between energy consumption and economic development. By comparing the forecasting methods of clean energy demand, it is found that the energy consumption elasticity coefficient method is used to measure and predict the growth ratio of energy consumption, and the figure in the next few years is measured. The software has self-built optimization model, reflects energy supply and demand fluctuations, and generates reports. It can make decision support for regional clean energy system planning, miscalculation and clean energy demand forecasting.
Effects of Pig Manure Composts on Lettuces Quality and Nitrogen/Phosphorus Utilization Efficiency in Huang-Huai Plain
Authors: Liu Shasha , Li Bing , Zhang Gubin , Feng Xiang , Yang Po , Guo Lin , Li Zitao , Li Zhijuan , Sun Xiaodan
Published: November 2019

The prevailing problems in countryside, such as excessive use of chemical fertilizer and large amounts of livestock manure, need to be addressed urgently. In order to optimize the amount of applied organic fertilizer, the experiment was carried out in the planting-breeding combined circular agricultural area of Huang-Huai plain and the effects of pig manure fertilizer amounts on lettuces yields, quality and nitrate/phosphorus utilization efficiency were investigated. It was found that the replacement of chemical fertilizer with organic fertilizer had no significant effects on the N and P content of lettuces when treated with the same amounts of fertilizer. However, it could improve its yield, quality, and nitrogen/phosphorus utilization efficiency. When the ratio of organic fertilizer replacement was 25%∼75%, the nitrate and nitrite content of lettuces were reduced by 19.41% and 73.33% compared with the chemical fertilizer treatment. The nitrogen and phosphorus utilization efficiency in the 75% organic fertilizer replacement were highest, which were 30.4%/44.9% higher than that of chemical fertilizer respectively. Above all, the 75% organic fertilizer with 25% fertilizer group had the best effect on the yield of lettuces, improving the quality and utilization efficiency of nitrogen and phosphorus fertilizer. The results could provide an important scientific basis for determination of regional vegetable planting fertilizer and reduce the non-point source pollution risk.
Assessment of urban land cover change base on Landsat satellite data: A case study from Hanoi, Vietnam
Authors: Tran Ducthien , Xu Dawei , Liu Bingxi
Published: November 2019

Rapid urbanization process is accelerating the dramatic transformation of urban land cover, creating strong economic, social and environmental impacts. Many studies have achieved significant achievements in the application of Landsat satellite data to assess the land cover change. Remote sensing images of contain the necessary spectral and spatial features of the various objects. The Normalized Difference Vegetation Index (NDVI) is utilized to analyze remote sensing images of landsat satellite data and is one of the most widely used numerical indicator for calculating the visible (VIS) and near-infrared bands (NIR) of the electromagnetic spectrum. In this study, the NDVI based classification has indicated about significant change in land cover in Hanoi, Vietnam from 2001 to 2017. The study results show that a major change has been found in the vegetation cover area where about 56 km2 (accounts for 12.3%) area has been lost during the period from 2001 to 2017. This study demonstrates the importance of considering land cover change to improve the quality and optimizing the model of land use in urban areas.
Comparison of spatial interpolation methods for mercury content in soil of contaminated farmland in Tongren
Authors: Song Xuelian , Ruan Xirui , Zhang Wen , Zhang Hua , Huang Guopei , Wang Zhiwei , Zhong Li , Wang Puchang
Published: November 2019

Taking mercury-contaminated farmland in Tongren city, Guizhou province as study area, we conducted five interpolation methods, including inverse distance weight, radial basis function, global polynomial, local polynomial and kriging, for the collected soil mercury content data. The interpolation results were evaluated by cross validation. The results indicated that the five methods can accurately reflect the spatial distribution characteristics of the study area and the interpolation effect and precision of kriging method are optimal. In kriging method, the accuracy of removing second-order trends is highest, and the interpolation effect of exponential model is the best. The variation function model of kriging method shows that soil mercury content in this region is mainly affected by natural factors, but less affected by random factors.
Study on Environmental Effects of Different Covering Measures on Spring Maize Planting in the Loess Plateau
Authors: Zhang Ruiqing
Published: November 2019

Covering farming techniques is an effective means of protecting and managing soils in arid, semi-arid and sub-humid and drought-prone areas, and is a change to traditional farming systems. This technology can regulate the “water, fertilizer, gas, heat” of farmland soil, change the physical and chemical properties and environmental quality of soil in arid areas, and effectively solve a series of problems caused by drought and irrational farming. Through different farming cover measures, In order to achieve stable production and high yield, it has important promotion value in the loess area. Through comprehensive research on the relevant research and demonstration experience of predecessors, this paper deeply studies the growth and development of spring maize and soil water and fertilizer effects under different cropping practices. It is found that different coverage measures have significant gain effects on soil moisture and fertility. The increase in corn production has a positive effect.
Explicit dynamic analysis of coal gangue particles impacting the metal plate
Authors: Bo Chen , Yang Yang , Xin Zhengyuan
Published: November 2019

To study the stress and strain of the tail beam and the change of the movement state when coal gangue particles impact the tail beam of the hydraulic support, coupled with the differences of impact results between coal rocks with different materials, this paper uses the method of joint simulation by Hypermesh and Workbench. Firstly, using the software Hypermesh to pre-process the impact model, and then importing the grid file into the finite element analysis software workbench. Finally, using the Explicit Dynamic module of Workbench to simulate and analyze the impact behavior of different coal gangue particles. The results show that, compared with gangue, the stress and strain, as well as the dynamic response of the metal plate caused by coal is smaller. This study can provide a reference for the study of dynamic characteristics of hydraulic support, and a research basis for the realization of coal gangue vibration identification method.
Study on Iterative Method of Nonlinear Finite Element Analysis for High Arch Dam
Authors: Wang Zhiqiang , Niu Jingtai
Published: November 2019

The nonlinear FEM can simulate the real working behavior of arch dam, but its result is related to iterative method and convergence control standard. This paper proposes iteration convergence criterion based on two iterative methods of Newton iterative method and modified Newton iterative method. Taking Xiluodu arch dam as an example, the article has conducted research to the problems above, thus obtaining some beneficial conclusions.
Direct Shear Test of Silty Clay Based on Corrected Calculating Model
Authors: Sun Zhaohui , Bian Hanbing , Wang Chenyu , Zhang Saize , Qiu Xiumei
Published: November 2019

Direct shear test is one of the common method to study the parameters of shear strength and shear strength of soil. However, the current standard of geotechnical test method does not consider the calculation error caused by the change of shear area during shear process. In this paper, the direct shear test corrected calculation model considering effective shear area is established. This model shows that the test values of shear stress and normal stress are lower than the corrected values with the decrease of effective shear area, and the errors between them will increase with the increase of relative shear displacement. The analysis of the direct shear test results of silty clay shows that the errors between the test and corrected shear stress values are also related to the normal stress. The errors will increase with the increase of the normal stress. The shear strength parameters after correction tends to decrease. The effect of the corrected model on the cohesion is more significant than internal friction angle, and the effect on internal friction angle can be neglected approximately. On the basis of Mohr-Coulomb criterion, a shear strength criterion based on the corrected calculation model is established, which can be used to calculate the true shear strength parameters more accurately.
Research on perfermance improvement of constructed wetland wastewater treatment system
Authors: Mao Yuting , Huang Haiqin
Published: November 2019

Constructed wetland is a kind of wastewater ecological treatment technology. It has the advantages of low investment, convenient operation and management, stable water quality, and has certain landscape effects. Therefore, it is widely used in the field of wastewater treatment. However, this technology still has certain problems in practical engineering applications, such as irregular design and clogging, resulting in limited service life and processing performance of the wetland. The type selection of constructed wetlands, matrix type and particle size, plant type and configuration, and water inflow mode and operating parameters are the main factors affecting the operating life and purification effect of constructed wetlands. Based on the author’s practice, the article introduces in detail the current process structure, basic design methods and economic and technical comparison of constructed wetland wastewater treatment for reference by relevant scientific research and design units.
Effect of Different Tillage Managements on Soil Physicochemical Properties and Crop Yield
Authors: Liu Zhe , Lei Na
Published: November 2019

In order to explore the effects of different tillage managements on soil physical-chemical properties and crop yield in Tangyu town, Meixian County of Shaanxi Province, the soil physical-chemical properties and crop yield were analyzed. The study was conducted at the Qinling Field Monitoring Center Station in early September 2017, which included three tillage managements: no tillage (NT), mouldboard plow tillage (MT) and soil subsoiling tillage (ST), the soil organic matter, total nitrogen, ammonium nitrogen, available potassium, soil temperature and maize grain number per ear and yield in the project area were measured. The results showed that the NT and ST managements could better buffer and maintain the change of soil temperature, reduced soil pH value compared with MT management. NT and ST managements were helpful to increase the content of total nitrogen, organic matter, ammonium nitrogen and available potassium, soil organic matter(SOM) content under NT and ST managements was 49.6% and 31.7% more than that under MT management in the 0–10 cm soil layer, The order of total nitrogen content was ST>NT>MT, and available potassium content was NT> ST>MT in the 0–30 cm soil layer, there was no obvious difference between NT and ST managements in improving soil nutrients. Meanwhile, NT and ST managements increased maize grain number per ear and yield. Thus, it was recommended to use NT and ST managements to improve soil quality and increase crop yield, and was suitable for sustainable agricultural development.
Ecological Footprint Evaluation Model of Petrochemical Industry Based on Energy Theory
Authors: Zhao Yu , Bai Xiaoqian
Published: November 2019

This paper establishes an ecological footprint model based on energy theory to calculate the ecological footprint of petrochemical industry. The results show that the industrial structure of petrochemical industry is single and the ecological environment is seriously damaged. The economic and social benefits created cannot compensate for the ecological environment cost of industrial development.
Distribution of Soil Nutrients in Loess Hilly and Gully Area
Authors: Ya Hu , Lu Zhang , Jie Cheng , Jing Wei
Published: November 2019

To understand the spatial distribution characteristics of soil nutrients after reclaiming the land in the loess hilly and gully region. We collected the soil profile data of 2m soil layer from the end of the ditch to the head of the ditch. The results showed that: (1) The average available phosphorus, available potassium and organic matter content of the soil in the gully area of the loess hilly and gully region were at a low level. The content of average available phosphorus and organic matter decreased first and then increased with the increase of soil depth. The content of average available potassium decreased with the depth deepening. The gully soil was alkaline and the pH value along with the soil depth. The increase is gradually increasing. (2) The content of available phosphorus gradually decreased, and the content of available potassium and pH value gradually increased. The spatial distribution characteristics of organic matter are similar to the spatial distribution of available phosphorus, and the content of available phosphorus is enriched below the trough end to the middle of the gully.
Research on the Water Diversion Ratio Characteristics of the Plain River Network--A Case Study of the Channel in Zhangjiagang
Authors: Wang Ziyue , Li Yiping , Weng Shenglin , Zhang Jinglin , Hu Tan
Published: November 2019

This study combined numerical simulation with field observation, and this study took the classical bifurcated river of Zhangjiagang as an example and built a two- dimensional hydrodynamic model of the river course upon it. In addition, this project studied the influencing factors and the mechanism of the flow diversion ratio in the plain river network and established a formula to estimate the flow diversion ratios in plain river networks with ridge regression. The results show that: (1) the water diversion ratio in plain rivers has a positive correlation with the roughness, the ratio of the width of the tributary to that of the main channel and the water level differences. The water diversion ratio has a negative correlation with the mainstream discharge. (2)The mainstream discharge and the ratio of the width of a tributary to that of the main channel are two dominant factors ofthe flow diversion ratio.(3)By establishing an equation for the water diversion ratio, the water diversion ratio in the plain river network can be predicted.
Calculation of Internal Force and Deformation of Overlying Soil Corrugated Arch Bridge Based on Plate and Shell Theory
Authors: Zhao Ruipeng
Published: November 2019

The shell is the general name for the flat plate and the shell. The mechanics of the plate and shell are similar to those of the elastic mechanics. The differential plate element is taken at any point in the plate or shell. From the perspectives of statics, geometry and physics, the equilibrium differential equations and geometric equations corresponding to the plate or shell are derived. And physical equations, these equations reflect the relationship and constraints between internal and external forces, strain and displacement, strain and stress. Under certain boundary conditions, the unknowns are determined by the above related basic equations.
Combined Application of Multiple Support Forms in Design of Large Deep Foundation Pits
Authors: Hu Qi , Xie Jiawen , Fang Huajian , Lou Zefeng , Zhu Xiang , Huang Xingdi
Published: November 2019

With the constant exploitation of underground space, the single support pattern is not able to meet the needs of the foundation ditch design. This paper is based on a design case of the large-deep foundation ditch in Hangzhou and took the different geological environment requirements into consideration. In this paper our research team put forward the composite design of support pattern which adopts steel support, bored grouting pipe, soil nailed wall etc. We hope this paper can provide suggestions and references for other analogous projects.
Research on Interaction of Pile - Anchor Retaining Structure and Proposed Pile-Raft Foundation
Authors: Liu Zeyong , He Shaoheng , Shang Yuequan , Sun Hongyue
Published: November 2019

During the excavation of the foundation pit, the interaction between the foundation pile anchor support structure and the proposed pile group raft foundation will affect the passive earth pressure of the support pile and the foundation pit uplift. In this paper, the finite element software ABAQUS was used to establish a foundation pit excavation model for two foundation pits with and without group piles. Through comparative analysis, the interaction between the pile-anchor support structure and the pile-slab foundation will affect the passive earth pressure of the supporting structure. As the depth of excavation increases, the earth pressure in the passive zone of the supporting structure gradually increases. Results have shown that the variation of the spacing between the pile foundation and the supporting structure will have a greater impact on the passive earth pressure. The research results in this paper summarize the experience of foundation pit construction and provide a numerical theoretical basis for the construction of similar deep foundation pits, which is of great significance for optimizing the design and construction of deep foundation pits.
A Review and Expectation on Land Engineering Reclamation Research--Using Bibliometric Method Based on Web of Science
Authors: Sun Yingying , Ling Li , He Lirong
Published: November 2019

To verify the international development of land engineering reclamation research, so as to provide data analysis result for the researchers, keywords included in the meaning of land engineering were selected, and related articles on web of science between 1980 and 2016 were reviewed. The results concluded that: 955 articles on land reclamation engineering from 99 countries were published from 1980 to 2016, annual trend of articles was in line with the law of linear. Articles from countries included China, America, England, Spanish made the strongest influence, and University of Chinese Academy of Sciences published the most articles. There is a growing concern on engineering reclamation research all over the world. Further researches on ecology and environmental sciences, agriculture, biodiversity protection, engineering science, business economics will be taken in the future.
Environmental problems in the mining of metal minerals
Authors: Luo Yuhu
Published: November 2019

During the mining of mineral resources, it will inevitably cause problems in the mine environment. According to the different ways of expressing environmental problems in mines, they can be divided into three categories: geological disasters, environmental damage and environmental pollution. Among the three mine environmental problems, environmental pollution has characteristics such as concealment, post-hazard hysteresis, watershed diffusion and accumulation, which cause serious damage to the mine environment. This paper focuses on the current status of environmental pollution problems in metal mining.
Differences in properties of long-term planting of different formulated soils
Authors: Lu Yangjie , Guo Zhen , Wang Yike , Cao Tingting
Published: November 2019

The characteristics of soil organic carbon, polysaccharides and calcium carbonate content in different proportions of compound soil were studied in the compound soil of arsenic rock zone and sand with rotation for 2 years, and the ripening of the mixed soil of arsenic rock zone and sand in different proportions was revealed. The results showed that the ratio of easily oxidized organic carbon in the 1:2 ratio of arsenic rock zone to sand is the highest in total organic carbon, the activity of organic carbon is the highest. And the content of polysaccharides and calcium carbonate in soil is higher, the water-soluble aggregates in soil were better developed.
Study on composite solid alkali-activated slag/fly ash concrete
Authors: Zhou Jianmei
Published: November 2019

Through FTIR, SEM/EDS and XRD analysis of hydration products of slag/fly ash concrete paste activated by composite solid alkali, the activation effect of composite solid alkali activator on slag/fly ash system was studied. The results show that the hydration products of the excitation system are mainly C-S-H gels, and the crystallization of C-S-H gels with 28 days hydration age tends to be perfect. The hydration products have good bonding and compact structure, which greatly improves the strength of the matrix. The damage pictures of 28-day-old C30 concrete blocks after compression test further show that the composite solid alkali activator has a good activation effect on slag/fly ash system.
Numerical simulation of thermal radiation distribution of large-scale crude oil storage tank
Authors: Zhou Feng
Published: November 2019

When the fire of a large-scale crude oil storage tank occurs, the fire source will emit large heat radiation which can induce not only serious economic losses, but also casualties. This paper investigated the influence of full-surface fire occurring in a crude oil storage tank on the adjacent tanks by numerical simulation based on the fire dynamic simulation software (FDS). Firstly, the combustion model of 105 m3 crude oil storage tank was constructed to reproduce the evolution behavior of the flame and smoke after the fire of the storage tank. The distributions of temperature and heat radiation value of adjacent storage tanks of crude oil storage tank were analyzed. The results show that a warning line with a radius of 57.77 m should be established to reduce the personnel and equipment damage caused by heat radiation when a full-surface fire occurs in the storage tank. This research can provide a technical basis and decisionmaking reference for the check computation of the fire-fighting capacity of fixed fire- fighting facilities, tactical arrangements of fire-fighting and rescue, and emergency rescue.
Distribution characteristics of soil moisture of small watershed in gully catchment of the Loess Plateau of China
Authors: Dong Qiguang , Han Jichang , Luo Lintao , Wang Huanyuan , Lei Na , Liu Zhe , He Jing
Published: November 2019

The temporal dynamics and spatial distribution characteristics of soil moisture in typical slope and gully of Jiulongquangou small watershed were studied in the hilly and gully region of the Loess Plateau of China. The average soil water content of each slope position showed a wave shape with time, and the change trend was: decreasing, increasing, decreasing and increasing. Due to the catchment in the gully, the average soil water content is the largest in the gully, and it changes more with the seasons. The profile soil moisture content characteristics at various slope positions are increased with the soil depth increasing, and the spatial variability of average soil water content in each layer depth is slightly reduced. The spatial variability of soils in different layers under different slopes is slightly fluctuating. However, due to the recharge of interflow and the consumption of roots, there is a large variability in the middle level of the gully and foot of slope, indicating that the interflow in the study area is a factor that must be considered. On the whole, in the small watershed of the gully region of the Loess Plateau, the topographic conditions affect the distribution characteristics of soil moisture, and the gully has obvious water collecting effect.
Crustal Movement Characteristics in the North-eastern Region of the Qinghai-Tibet Plateau Based on GPS reference station
Authors: Ma Haiping , Wu Yanqiang , Feng Jiangang , Li Xiaofeng , Xu Hui , Wang Qian
Published: November 2019

To discuss the crustal movement characteristics in the northeastern region of the Qinghai-Tibet Plateau, the crustal deformation state and the annual movement rate of the GPS continuous baseline time series between the station in the stable blocks and the stations inter the Qinghai-Tibet Plateau are calculated based on the GPS data observed by the continuous stations in the Qinghai-Tibet Plateau and surrounding areas since 1999. The results demonstrate that the compression and shortening movements between the Qilianshan block, the Qaidam block, the Bayan Har block and the two rigid blocks, Alxa block and the Ordos block, are relatively strong. However, the extension or compression rate between the two rigid blocks and the Qilianshan seismic belt, the Longzhong basin tectonic region and the South China block is quite small. It is indicated that the compressed or extended movement between the suture zone of the two blocks and the northeast edge of the Qinghai-Tibet Plateau is small. It is illustrated that certain strain energy may accumulate in the region and have a relatively high potential for strong earthquakes.
Surface Deformation over Permafrost Environment of the Tanggula Section in the Qinghai-Tibet Plateau Using Active Microwave Spectral Imagines
Authors: Wang Zhiwei , Yue Guangyang , Wu Xiaodong , Zhang Wen , Song Xuelian , Wang Puchang , Wu Jiahai
Published: November 2019

Changes of permafrost and the active layer affect geophysical process, water circulation, biological diversity and carbon storage. The monitoring of ground surface deformations is crucial and necessary to estimate the degradation of permafrost environment. In this study, the ground motions of the Tanggula section in the Qinghai- Tibet Plateau (QTP), a region with limited in situ measurements at spatial scale, have been investigated by the small baseline SAR interferometry (SBAS-InSAR). In total, 17 C-band ENVISAT ASAR images (acquired from January 1, 2009 to August 19, 2010) were employed. The results show that the ground surface motion was primarily in the range of – 7.6 mm per year to 6.7 mm per year, and the correlation coefficients and the P-values between deformations and Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperatures (LSTs) were ranged from -0.24 to -0.47 and from 0.09 to 0.41, respectively. And the precision file of the surface displacement rates map is showed that the estimated displacement velocity is reliable. Our study has observed that the majority of ground surface (approximately 70%) was relatively stable in the study period with displacements in the range of -2 mm per year to 2 mm per year and the ground subsidence is larger than the ground heave, implying the necessity of time series deformations surveillance derived from satellites in the permafrost environment.
Effects of Vegetation Construction on the Soil Environment in North China
Authors: Li Gang
Published: November 2019

Vegetation construction is one of the most important measures of ecology restoration in arid and semi-arid. Reasonable vegetation construction can improve the local soil environment and quality effectively. Thus, promote the vegetation restoration and ecology environment reconstruction. However, because of the different factors such as the plant trees, the ecology environment of vegetation construction in the vegetation construction, there are distinct influence on soil environment. This research choose the articles which related vegetation constrction and soil environment in arid and semi-arid areas in China as the research object, in which we foucs on the influence of soil moisture, soil organic matter and soil total nitrogen by artificial vegetation restoration.
Cultivation and Protection of Forest Resources
Authors: Jin Binbin
Published: November 2019

Forest cultivation and forest resource protection is an important part of forestry ecological construction, an important measure to promote tree growth, improve forest quality and increase forest efficiency, and an important means to maintain ecological environment balance and build a harmonious development of good man and nature. Based on this, this paper studies the necessity of the cultivation and protection of forest resources, probes into the methods of ecological, economic and social benefits of forest resources, and points out the unreasonable management concepts that still exist in the current forest cultivation work, the lack of attention to science and technology, the untimely cultivation and the lack of financial support, etc. And put forward the relevant countermeasures and measures to further strengthen the cultivation and protection of forest resources in China.
The Variation of Land Temperature in Different Years of Sandstone and Sand
Authors: Liu Yangyang , Guo Zhen , Li Juan
Published: November 2019

In order to analyze the effect of different ages of sandstone and sand on soil temperature, this study selected the compound soil with 2 years of soil formation and 9 years of soil formation, using loess: sand 1:2, sandstone: sand 1:1, sandstone: sand 1:2, sandstone: sand 1:5, sandstone: sand 0:1 different proportions of soil for research, using geothermal meters for different soil layers (5cm, 10cm, 15cm, 20cm, 25cm) temperature observation. The results show that: 1. The variation of ground temperature in different soil layers of 2 and 9 years of soil formation shows 5cm>10cm>15cm>20cm≈25cm, the basic performance is that the temperature of the soil in the 9- year-old compounding soil is lower than the temperature of the soil in the soil for 2 years. 2. The soil of 2 years of soil formation is characterized by sandstone in different soil layers: sand = 1:2, the highest temperature, sandstone: sand = 0:1 compound soil temperature is the lowest; soil formation 9 years compounding The soil has the lowest loess in different soil layers: sand = 1:2, and the soil in different soil layers has better cushioning properties. 3. During the period from 8:00 to 20:00, with the change of measurement time, the trend of ground temperature change can be fitted by the polynomial equation y=ax2+bx+c, which is most obvious with 5cm soil layer, with soil layer As the depth increases, the slope of the polynomial curve gradually decreases. 4. In the soil of 9 years of compounding, the time when the sandstone of sandstone: 1:1 soil reached its peak was postponed from 14:00 to 16:00, and the peak of loess: sand = 1:1 the original 16:00 point was delayed until 18:00, and the time when other compounded soils reached their peak was 16:00.
Water Resources Shortage Risk Prediction of Shanxi Province Based on Fault Tree Analysis and Markov Chain Model
Authors: Wei Yang
Published: November 2019

The shortage of water resources that mankind is facing is also increasing. Shanxi province is one of the most famous traditional heavy-industry bases in China. And it is also one of the most serious water-shortage provinces in China. At present, the status of coal in the world energy structure is declined. Shanxi province is facing a critical period of transformation of industrial structure. How to solve the problem of water shortage and support the rapid development of social economy in Shanxi province is to be solved urgently in the area. Based on the specific situation of water shortage in Shanxi Province, this paper discusses the Markov prediction method and fault tree analysis model for the risk of water shortage in Shanxi Province, and we provides suggestions to prevent and solve water resources shortage in the process of economic and social development in Shanxi province.
Contribution Rate of MWD Survey Error Sources on Well Trajectory Measurement Error
Authors: Diao Binbin , Gao Deli , Jiang Chuang
Published: November 2019

Since the number of error sources is too large and the standard deviations of the error sources are really difficult, it is of great practical significance to study the contribution rate of each error source on the wellbore trajectory measurement error. The error sources of well trajectory measurement using MWD (Measurement While Drilling) are introduced, and the contribution rate calculation model of each error source on well trajectory measurement error is established. The contribution rate of each error source on well trajectory measurement error is analyzed with an example. The research shows that the error sources contribute most to the well trajectory measurement error for each main semi-axes of the error ellipsoid are different; the error sources contribute most to the well trajectory measurement error are different in the vertical section, the inclined section and the horizontal section; the error source associated with the sensors contributes least to the well trajectory measurement error compared with other sources of error. In drilling engineering, it is necessary to give the standard deviation of the main error sources as accurately as possible to better evaluate the well trajectory measurement error.
Three-dimensional cartilage tissue regeneration system harnessing goblet-shaped microwells containing biocompatible hydrogel
Authors: Udomluck Nopphadol , Kim Sung-Hwan , Cho Hyunjoo , Park Joong Yull , Park Hansoo
Published: November 2019

Differentiation of stem cells into chondrocytes has been studied for the engineering of cartilage tissue. However, stem cells cultured two-dimensionally have limited ability to differentiate into chondrocytes, which led to the development of three-dimensional culture systems. A recently developed microtechnological method uses microwells as a tool to form uniformly sized spheroids. In this study, we fabricated an array (10 × 10) of goblet-shaped microwells based on polydimethylsiloxane for spheroid culture. A central processing unit (CPU) was used to form holes, and metallic beads were used to form hemispherical microwell geometry. The holes were filled with Pluronic F-127 to prevent cells from sinking through the holes and allowing the cells to form spheroids. Viability and chondrogenic differentiation of human adipose-derived stem cells were assessed. The fabrication method using a micro-pin mold and metallic beads is easy and cost-effective. Our three-dimensional spheroid culture system optimizes the efficient differentiation of cells and has various applications, such as drug delivery, cell therapy, and tissue engineering.
Customizable, engineered substrates for rapid screening of cellular cues
Authors: Huethorst Eline , Cutiongco Marie FA , Campbell Fraser A , Saeed Anwer , Love Rachel , Reynolds Paul M , Dalby Matthew J , Gadegaard Nikolaj
Published: November 2019

Biophysical cues robustly direct cell responses and are thus important tools for in vitro and translational biomedical applications. High throughput platforms exploring substrates with varying physical properties are therefore valuable. However, currently existing platforms are limited in throughput, the biomaterials used, the capability to segregate between different cues and the assessment of dynamic responses. Here we present a multiwell array (3 × 8) made of a substrate engineered to present topography or rigidity cues welded to a bottomless plate with a 96-well format. Both the patterns on the engineered substrate and the well plate format can be easily customized, permitting systematic and efficient screening of biophysical cues. To demonstrate the broad range of possible biophysical cues examinable, we designed and tested three multiwell arrays to influence cardiomyocyte, chondrocyte and osteoblast function. Using the multiwell array, we were able to measure different cell functionalities using analytical modalities such as live microscopy, qPCR and immunofluorescence. We observed that grooves (5 μm in size) induced less variation in contractile function of cardiomyocytes. Compared to unpatterned plastic, nanopillars with 127 nm height, 100 nm diameter and 300 nm pitch enhanced matrix deposition, chondrogenic gene expression and chondrogenic maintenance. High aspect ratio pillars with an elastic shear modulus of 16 kPa mimicking the matrix found in early stages of bone development improved osteogenic gene expression compared to stiff plastic. We envisage that our bespoke multiwell array will accelerate the discovery of relevant biophysical cues through improved throughput and variety.
Chemical Decontamination of Hazardous Drugs: A Comparison of Solution Performances
Authors: Simon Nicolas , Odou Pascal , Decaudin Bertrand , Bonnabry Pascal , Fleury-Souverain Sandrine
Published: November 2019

Objectives

Over the past 40 years, numerous actions have been undertaken to decrease the contamination of hospital facilities by intravenous conventional antineoplastic drugs (ICADs) such as centralizing compounding in pharmacies, using personal protective equipment, specific compounding, or infusion devices. As recently proposed in the  monograph, an additional specific decontamination step must be envisaged. A recent literature review analysed and discussed the different solutions tested in terms of decontamination efficacy. This article aims to discuss the performance of these solutions in the framework of aseptic compounding.

Methods

The same dataset used in the previous literature review was reanalysed according to other parameters so as to select decontamination solutions: overall decontamination efficiency (EffQ), tested contaminants, and the risks of use in daily practice.

Results

Using an EffQ threshold of 90% resulted in discarding 26 out of the 59 solutions. Solutions were tested differently: 8 on 1 contaminant, 11 on 2 contaminants, and 14 solutions on between 3 and 11 contaminants. Three risks were identified to help make choices in routine practice: the mutagenicity of degradation products, the safety of operators and facilities, and respect for the aseptic environment.

Conclusions

From the results, performance is discussed according to specific situations: a one-time incident or the basic chemical contamination due to daily practice. Accordingly, the decontamination solution selected then required a risk analysis and an evaluation before implementing it in the daily practice of a compounding unit.
Nod2 Protects the Gut From Experimental Colitis Spreading to Small Intestine
Authors: Al Nabhani Ziad , Berrebi Dominique , Martinez-Vinson Christine , Montcuquet Nicolas , Madre Chrystele , Roy Maryline , Ogier-Denis Eric , Dussaillant Monique , Cerf-Bensussan Nadine , Zouali Habib , Daniel Fanny , Barreau Frédérick , Hugot Jean-Pierre
Published: November 2019

Background and Aims

Nucleotide oligomerization domain 2 [NOD2] mutations are key risk factors for Crohn’s disease [CD]. NOD2 contributes to intestinal homeostasis by regulating innate and adaptive immunity together with intestinal epithelial function. However, the exact roles of NOD2 in CD and other NOD2-associated disorders remain poorly known.

Methods

We initially observed that NOD2 expression was increased in epithelial cells away from inflamed areas in CD patients. To explore this finding, Nod2 mRNA expression, inflammation, and cytokines expression were examined in the small bowel of wild-type [WT], Nod2 knockout and Nod2 mutant mice after rectal instillation of 2,4,6-trinitrobenzene sulphonic acid [TNBS].

Results

In WT mice, Nod2 upregulation upstream to rectal injury was associated with pro-inflammatory cytokine expression but no overt histological inflammatory lesions. Conversely, in Nod2-deficient mice the inflammation spread from colitis to ileum and duodenum.

Conclusions

Nod2 protects the gut from colitis spreading to small intestine.
Complete revascularization reduces cardiovascular death in patients with ST-segment elevation myocardial infarction and multivessel disease: systematic review and meta-analysis of randomized clinical trials
Authors: Pavasini Rita , Biscaglia Simone , Barbato Emanuele , Tebaldi Matteo , Dudek Dariusz , Escaned Javier , Casella Gianni , Santarelli Andrea , Guiducci Vincenzo , Gutierrez-Ibanes Enrique , Di Pasquale Giuseppe , Politi Luigi , Saglietto Andrea , D’Ascenzo Fabrizio , Campo Gianluca
Published: November 2019

Aims

The aim of this work was to investigate the prognostic impact of revascularization of non-culprit lesions in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease by performing a meta-analysis of available randomized clinical trials (RCTs).

Methods and results

Data from six RCTs comparing complete vs. culprit-only revascularization in STEMI patients with multivessel disease were analysed with random effect generic inverse variance method meta-analysis. The endpoints were expressed as hazard ratio (HR) with 95% confidence interval (CI). The primary outcome was cardiovascular death. Main secondary outcomes of interest were all-cause death, myocardial infarction (MI), and repeated coronary revascularization. Overall, 6528 patients were included (3139 complete group, 3389 culprit-only group). After a follow-up ranging between 1 and 3 years (median 2 years), cardiovascular death was significantly reduced in the group receiving complete revascularization (HR 0.62, 95% CI 0.39–0.97, I  2 = 29%). The number needed to treat to prevent one cardiovascular death was 70 (95% CI 36–150). The secondary endpoints MI and revascularization were also significantly reduced (HR 0.68, 95% CI 0.55–0.84, I  2 = 0% and HR 0.29, 95% CI 0.22–0.38, I  2 = 36%, respectively). Needed to treats were 45 (95% CI 37–55) for MI and 8 (95% CI 5–13) for revascularization. All-cause death (HR 0.81, 95% CI 0.56–1.16, I  2 = 27%) was not affected by the revascularization strategy.

Conclusion

In a selected study population of STEMI patients with multivessel disease, a complete revascularization strategy is associated with a reduction in cardiovascular death. This reduction is concomitant with that of MI and the need of repeated revascularization.
Philosophical Solitude: David Hume versus Jean-Jacques Rousseau
Authors: Taylor Barbara
Published: November 2019

The philosopher meditating alone in his study is a cliché of western culture. But behind the hackneyed image lies a long history of controversy. Was solitude the ‘palace of learning’ that many learned people, religious and secular, perceived it, or a debilitating state of solipsistic misery and intellectual degeneracy, as its enemies described it? In the mid eighteenth century the debate became fiercely personal during a public quarrel between two philosophical luminaries: David Hume and Jean-Jacques Rousseau. In the 1760s Rousseau faced persecution from state and church authorities in France and Switzerland. Hume gave him refuge in England. The relationship rapidly turned toxic as the convivial Hume sought to manage his notoriously reclusive charge. Solitude became a casus belli in a war of words that fascinated intellectual Europe. But the fracas was more complex than it appeared. Who are we with, when we are alone? For Hume, no less than Rousseau, the question proved inescapable, in both his personal career and his philosophy. A closer look at two thinkers who, on the surface, were a study in opposites, reveals much about the vicissitudes of solitude in the life of the creative mind.
Existence of weak solutions to a dynamic model for smectic-A liquid crystals under undulations
Authors: Emmrich Etienne , Lasarzik Robert
Published: November 2019

A nonlinear model due to Soddemann et al. (2004, Shear-induced undulation of smectic-A: molecular dynamics simulations vs. analytical theory. Eur. Phys. J. E., 13, 141–151) and Stewart(2007, Dynamic theory for smectic-A liquid crystals. Contin. Mech. Thermodyn., 18, 343–360) describing incompressible smectic-A liquid crystals under flow is studied. In comparison to previously considered models, this particular model takes into account possible undulations of the layers away from equilibrium, which has been observed in experiments. The emerging decoupling of the director and the layer normal is incorporated by an additional evolution equation for the director. Global existence of weak solutions to this model is proved via a Galerkin approximation with eigenfunctions of the associated linear differential operators in the 3D case.