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Regional haze pollution has frequently occurred in China over the past several years, and this haze has hindered the development of the economy and harmed the health of people in China. Currently, several studies have analyzed the impact of different influencing factors on haze. However, few studies have comprehensively analyzed the influential factors of haze from different perspectives. In this paper, we utilized global and local regression models to explore the main influential factors on air quality index (AQI) in China from global and local perspectives. The results are as follows: (1) the AQIs of Chinese cities have significant positive spatial correlation, and higher values of AQI were typically found in Beijing-Tianjin-Hebei, Shandong, Henan, Shanxi and Shaanxi Province; (2) from a global perspective, as there is one unit of increase in the average AQI of one city's neighbors, the city's AQI will increase by 0.827 unit. An increase in the industrial structures and the number of civilian vehicles will also lead to an increase in the AQI, but the impact of precipitation is reversed; and (3) from a local perspective, there are spatial differences in the effects of different factors on the AQI. In northern China, an appropriate temperature reduction and an appropriate increase in atmospheric pressure is helpful for reducing haze pollution; however, opposing conditions are found in southern China. Compared with China's coastal cities, the increase in precipitation is more effective at reducing the AQI in inland cities. Compared with other cities, reducing the industrial structure and the number of civilian vehicles was more effective for haze management in Beijing, Tianjin, Shandong, Henan, Shanxi, and Shaanxi provinces. These results of this paper are helpful for government departments to formulate regionally differentiated governance policies regarding haze. Image 1 • Both natural and anthropogenic factors are used to detect their impacts on haze. • Identification of influential factors on haze pollution from global and local perspectives. • AQI of most cities are High-High (38.98%) and Low-Low (38.14%) clustering types. • A city's AQI increases 0.827 unit for every 1 unit addition in the average AQI of neighbors. • GWR result shows that there are obvious spatial differences of influential factors on AQI. This paper identifies the main influential factors and spatial differences of air quality in China. [ABSTRACT FROM AUTHOR]

The paper presents the optimization of the epoxidation process of crotyl alcohol on the Ti-MWW catalyst at atmospheric pressure, based on the Taguchi orthogonal array method. Shown are the influence of the most important process parameters, such a temperature, molar ratio of crotyl alcohol to H 2 O 2 , methanol concentration, Ti-MWW catalyst concentration and reaction time. The response functions characterizing epoxidation process were selectivity of transformation to 2,3-epoxybutan-1-ol with respect to reacted crotyl alcohol – S 2,3EB1O/CA , conversion of crotyl alcohol C CA , yield of 2,3-epoxybutan-1-ol W 2,3EB1O. Based on the calculated signal/noise ratios for individual parameters of the process, their impact on all output parameters was determined and optimal process conditions were determined to reach its the maximum. The empirical verification of this process was also performed by comparing both output parameters predicted and achieved in the tests. This method allows limiting the number of tests required to reach the wished test results, diminution the time needed course for their achievement, and at the same time their expenses. [ABSTRACT FROM AUTHOR]

In this paper, the reductive N-formylation, methylation and cyclization of amines with carbon dioxide (CO 2) using sodium borohydride (NaBH 4) at atmospheric pressure, via a one-pot two-step procedure, is presented. Formato borohydride (NaBH n (OCHO) 4-n), in situ formed in the reaction of NaBH 4 with CO 2 , as an efficient agent to promote the corresponding reaction, and the mechanism is proposed on the basis of experiments. This wide substrate scope and simple operational methodology also facilitates the effective synthesis of formamides, methylamines, benzimidazoles and other heterocyclic compounds avoiding high temperature and pressure. [Display omitted] • Catalyst-free stepwise reduction of CO 2 with amines to N -substituted compounds. • This methodology realized the chemical conversion of carbon dioxide at atmospheric pressure. • It is an efficient synthetic method for formamides, methylamines and heterocyclic compounds. [ABSTRACT FROM AUTHOR]

Barodontalgia is not a pathology but a symptom of a subclinical oral problem that, although rare, may affect patients subjected to atmospheric pressure changes and have an influence on flights. This paper aims to discuss the clinical characteristics of pathologies related to the etiology of barodontalgia, as well as differential diagnoses, treatments, and prevention. This paper reports a case of a Brazilian air force officer who went to the Santos Dumont Air Force Dental Clinic reporting pain in the anterior maxillary during a flight. An endodontic treatment followed by periradicular surgery was performed, in order to quickly seal the bone lesion and to avoid new cases of barodontalgia. This work demonstrated a successful approach of a periradicular lesion solved by surgical treatment in order to avoid new cases of barodontalgia during flights. In addition, this paper highlights the importance of deepening knowledge on this event and the need for periodic oral and dental assessment, as well as conclusive treatment in aircrew members in order to prevent aircraft accidents. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, computational fluid dynamic (CFD) analysis and experiments have been carried out to study the effect of nozzle pressure ratio, i.e. the ratio of inlet pressure to atmospheric pressure, and the pitch circle diameter of the control jets to regulate the base pressure. The variables considered for the analysis as well as the experiments are the nozzle pressure ratio (NPR), the Mach number (M) and the pitch circle diameter (PCD) of the control jets. The area ratio considered for the study is kept constant at 4.84 while the length to diameter (L/D) ratio of an enlarged duct is set constant at 5. The inertia parameter considered for the study is Mach number. The Mach numbers considered for study are 1.5, 2.0, and 2.5. The nozzle pressure ratio considered for study are 2, 5 and 8. Three different pitch circle diameters of control jets considered for study are 13.1 mm, 16.2 mm and 19.3 mm. From the numerical simulations and the results of the experimental tests, it is found that the control jets are very beneficial to increase the base pressure at higher NPR when the jets issuing from the nozzles are under-expanded. The control jets were able to increase the base pressure value from 160% to 400% at nozzle pressure ratio 8. It is concluded that the parameter D3 is the most effective pitch circle diameter of the control jets to increase the base pressure. [ABSTRACT FROM AUTHOR]

In recent years, interest for petrochemical processes has been increasing, especially in refinement area. However, the high variability in the dynamic characteristics present in the atmospheric distillation column poses a challenge to obtain quality products. To improve distillates quality in spite of the changes in the input crude oil composition, this paper details a new design of a control strategy in a conventional crude oil distillation plant defined using formal interaction analysis tools. The process dynamic and its control are simulated on Aspen HYSYS ® dynamic environment under real operating conditions. The simulation results are compared against a typical control strategy commonly used in crude oil atmospheric distillation columns. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Shandong Peninsula, as a more developed region of economy and society in Shandong province even in the east coast of China, is facing challenges from resources and environment pressures. As the scope of economy expanding, the water''s restriction to the development of economy and society is more and more evident. This paper tried to track and assess the harmonious status between the water resource and environment''s Status and the development of economy and society in Shandong Peninsula in order to provide decision support for regional sustainability. This paper analyzed the water''s development situation through calculating the total amount of water recourses, the balance of water''s supply and demand and the utilization effects of water recourses and gave the aftereffect of environment because of inconsequential development and use. With Delphi and AHP methods, an appraisal index system was built including five aspects of harmony degree (A), sustainability degree (B), opening degree (C), stability degree (D) and controllability degree (E). The results showed that:1) Shandong peninsula belongs to the essence coordination type and the indexes of opening degree and sustainability degree are above the average level; 2)The economic increase of Shandong peninsula belongs to extensive mode and depends on amount input of funds, labor and the excessive consumption of resource; and 3)water resource becomes the main factor that constrained the coordination of economy, society and environment in Shandong peninsula. The paper provides quantitative gist to the majestic target of designing resource-saving based society. [Copyright &y& Elsevier]

Abstract: Aiming at strengthening the airtight-wall tightness, reducing its leakage rate, so that extinguishing the combustion in the burning area as soon as possible, this paper proposes the new ideas that the atmospheric pressure changes is important affecting factor to airtight-wall leakage rate in airtight burning area. Adopting the comprehensive research method of theoretical analysis, field measurement, and numerical calculation, this paper studies the influence law of the periodical change of the atmospheric pressure on the airtight-wall leakage rate, the results show that: the curve of underground pressure is sinusoid approximately; the atmospheric pressure changes is the main reason for the internal and external pressure difference of the airtight-wall; the gas exchange capacity of internal and external burning area is large, the gas exchange capacity of calculation example is more than 1400m3 every day. To reduce the firewall leakage rate, this paper proposes the specific solutions including building gas pressure balance room, strengthening airtight-wall tightness, and reducing the burning area volume, etc. [Copyright &y& Elsevier]

The atmospheric meteorology parameters of the earth, such as temperature, pressure, and humidity, strongly influence the propagation of signals in Global Navigation Satellite Systems (GNSSs). The propagation delays associated with GNSS signals can be modeled and explained based on the atmospheric temperature, pressure, and humidity, as well as the locations of the satellites and receivers. In this paper, we propose an optimized and simplified low cost GNSS base weather station that can be used to provide a global estimate of the integrated water vapor value. Our algorithm can be used to measure the zenith tropospheric delay based on the measured propagation delays in the received signals. We also present the results of the data measurements performed at our station located in the Tlemcen region of Algeria. [ABSTRACT FROM AUTHOR]

With the growing demand of power generated by wind energy, prediction of wind speed has become an important region for research. In this paper, wind speed is predicted using Generalized Regression Neural Network (GRNN) and Multi-layer perceptron (MLP) in 67 cities of India. The input variables used are: Longitude, Latitude, daily solar radiation- horizontal, air temperature, relative humidity, earth temperature, elevation, cooling degree-days, heating degree-days, atmospheric pressure. The MSE of the two models are compared and found that GRNN gives better result than MLP. The accuracy of GRNN and MLP are 99.99% and 97.974% for training phase and 98.85% and 95.23% for testing phase respectively. [ABSTRACT FROM AUTHOR]

In this paper, we study the influence of modifying the geometry of nanotexture on its electrical properties. Nanotexture is formed by an industrially feasible dry-chemical etching process performed entirely in atmospheric pressure conditions. A surface modification process is developed that allows low surface recombination velocities ( S eff,min ≤ 10 cm/s) on nanotextured surfaces. By simultaneously improving the surface passivation and the emitter diffusion processes, we achieve an equivalent passivation level ( V OC,impl ≥ 670 mV) for nanotextured surfaces to that of reference textured surfaces after applying either PECVD or ALD based deposition techniques. [ABSTRACT FROM AUTHOR]

In this paper, we propose an efficient method to remove haze from a single input image. Here, we presented an approach which is based on Fast Fourier Transform. Transmission map is refined by the dark channel prior method and Fast Fourier Transform. Finally the scene radiance is corrected using the visibility restoration model. Qualitative and quantitative results demonstrated that this method can effectively remove the bad weather condition and enhance the contrast of the input images and performs well in comparison with bilateral filtering. Moreover, the proposed method can significantly reduce the computational complexity. The use of Fast Fourier Transform in these images makes our approach faster by 88% in comparison to the bilateral filtering method. The main advantage of the proposed approach is suitable for images with too much of the sky background. Proposed method, due to its speed and ability to improve visibility, may be used in many systems such as surveillance, consumer electronics and remote sensing. [ABSTRACT FROM AUTHOR]

Gas emission is affected by many factors. Effects of atmospheric pressure on coal mine gas emission have become a rising concern. Basing on the gas emission at Y485 fully mechanized working face of Tangshan mine and atmospheric pressure, the paper had carried out online monitoring with sensors for 20 days continuously. Calculating the average values of atmospheric pressure and the expectation values of return air gas concentration of each hour on every monitoring date according to monitoring data, affection laws of atmospheric pressure to gas emission at fully mechanized working face were studied combining the weather and temperature of monitoring dates. It pointed out that the atmospheric pressure declines along with the rising of temperature and the gas emission at fully mechanized working face could be restrained if the atmospheric pressure rises, otherwise it could be promoted to release, the affection of variation of atmospheric pressure to gas emission was 0.0575%/hPa on cloudy day, and was 0.0446%/hPa on sunny day, and it was predicted that the peak time of gas emission at fully mechanized working face was from 12 o’clock to 16 o’clock according to the data processing results. [ABSTRACT FROM AUTHOR]

In this paper is aimed to study the augmentation of pool boiling heat transfer characteristics of different surfaces with water, experimentally at atmospheric pressure. There were four surfaces used, viz. untreated (Plain), treated by emery grateno. 2000 and treated with silicon oxide (SiOx) TF surfaces having nano-layer thickness of 100, and 200 nm. The thin film nanocoating was prepared by e-beam evaporation Systems. The surfaces were characterized with respect to contact angle, film thickness and surface roughness. After analyzing the data, it was found that thin film surface is superior to the treated and plain surface in view of boiling heat transfer coefficient. The result found that a maximum of 45.6%, 36.8%, and 10.5% enhancement in heat transfer co-efficient was observed for SiO x TF (200 nm), SiO x TF (100 nm), and treated surfaces respectively compared to plain surface at lower heat flux. Highest enhancement of heat transfer coefficient in thin film surfaces was due to capillary effect, better liquid spreading and high density active nucleate site. [ABSTRACT FROM AUTHOR]

Barometric MEMS pressure sensors must be calibrated at several temperatures and pressures. The fewer calibration points are needed to fulfill a sensor specification, the faster sensor production is. This paper proposes a polynomial approach for determining optimal sensor calibration, using the minimum number of calibration points necessary. In an experiment the framework is applied to the following sensor types: Bosch BMP085, Bosch BMP180, and EPCOS T5400. Influences of temperature operation range and pressure range are discussed in the experiment. Further, optimal calibration point suggestions are identified. [ABSTRACT FROM AUTHOR]

Gas emission is affected by many factors. Effects of atmospheric pressure on coal mine gas emission have become a rising concern. Basing on the gas emission at Y485 fully mechanized working face of Tangshan mine and atmospheric pressure, the paper had carried out online monitoring with sensors for 20 days continuously. Calculating the average values of atmospheric pressure and the expectation values of return air gas concentration of each hour on every monitoring date according to monitoring data, affection laws of atmospheric pressure to gas emission at fully mechanized working face were studied combining the weather and temperature of monitoring dates. It pointed out that the atmospheric pressure declines along with the rising of temperature and the gas emission at fully mechanized working face could be restrained if the atmospheric pressure rises, otherwise it could be promoted to release, the affection of variation of atmospheric pressure to gas emission was 0.0575%/hPa on cloudy day, and was 0.0446%/hPa on sunny day, and it was predicted that the peak time of gas emission at fully mechanized working face was from 12 o’clock to 16 o’clock according to the data processing results. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to develop optimum designs of oxygen sensor, technologies of sensors, and new methods of processing initial signals aimed at increasing metrological characteristics of oxygen sensor. We investigate the influence of external (atmospheric pressure, ambient temperature, availability of impurity) and internal factors of the system (design features of oxygen sensors, materials of electrodes and gaze-diffusion membranes, electrolyte structure) on sensors' metrological characteristics. The increase of metrological devices' characteristics to certain borders is reached by reducing the area of working electrode which leads to reduction of oxygen expenses on the analysis and respectively the influence of device on the object under study. Studying the influence of different factors on metrological characteristics of oxygen sensor, searching for optimum conditions of their application in definite situations will open new prospects for increasing technical characteristics of the oxygen gas analyzers. Furthermore, the determined optimum characteristics of sensors at this stage will be used to develop next generations of devices in future. [ABSTRACT FROM AUTHOR]

Abstract: The briquette oxygen-enriched gasification technology developed with traditional moving bed gasifier is a developing technology in line with our strategic policy of energy. In order to master the flow and reaction states of the existing gasifier, a computational fluid dynamics software was utilized to simulate in this paper. Based on the geometric model with atmospheric pressure gasifier corresponding to the actual operation, the two-way k-ɛ model, the fluid transport model and SIMPLE method was adopted to solve N-S equation and P1 model, so as to simulate internal temperature and components’ concentration fields. The simulation results provide theoretical foundation for further study on combustion in the gasifier, optimization of combustion process and guidance for production process improvement. [Copyright &y& Elsevier]

Copyright of Electronics & Electrical Engineering is the property of Electronics & Electrical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Gaseous plasma discharges are one of the most common means to modify the surface of a polymer without affecting its bulk properties. However, this normally requires the materials to be processed in vacuo to create the active species required to permanently modify the surface chemistry. The ability to invoke such changes under normal ambient conditions in a cost-effective manner has much to offer to enhance the response of medical implants in vivo. It is therefore important to accurately determine the nature and scale of the effects derived from this technology. This paper reports on the modification of poly(styrene) (PS) and poly(methyl methacrylate) (PMMA) using atmospheric pressure plasma processing via exposure to a dielectric barrier discharge (DBD). The changes in surface chemistry and topography after DBD treatment were characterised using water contact angle, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy. A marked increase in the surface oxygen concentration was observed for both PMMA and PS. An increase in surface roughness was observed for PMMA, but not for PS. These changes were found to result in an increase in surface wettability for both polymers. Adsorption of albumin (Alb) onto these substrates was studied using XPS and quartz crystal microbalance with dissipation (QCM-D). The rate of adsorption of Alb onto pristine PMMA and PS was faster than that on the DBD-treated polymers. XPS indicated that a similar concentration of Alb occurred on both of the treated surfaces. Deconvolution of the C1s XPS spectra showed that Alb is adsorbed differently on pristine (hydrophobic) compared to DBD-treated (hydrophilic) surfaces, with more polar functional groups oriented towards the upper surface in the latter case. The QCM-D data corroborates this finding, in that a more viscoelastic layer of Alb was formed on the DBD-treated surfaces relative to that on the pristine surfaces. It was also found that Alb was more easily replaced by larger proteins from foetal bovine serum on the DBD-treated surfaces. The viability of human lens epithelial cells on both of the DBD-treated polymer surface was significantly (P <0.05) greater than on the respective pristine surfaces. In addition, cells that adhered to the treated polymers exhibited a polygonal morphology with well spread actin stress fibres compared with the contracted shape displayed on the pristine surfaces. The results presented here clearly indicate that DBD surface modification has the capability to influence key protein and cell responses. [Copyright &y& Elsevier]

In this paper a study is presented on the connection between the atmospheric circulation over the Atlantic-European region and the occurrence of drought in the Romanian territory over the 1961-1990 WMO-established reference period. The large-scale atmospheric circulation is studied according to the classification proposed by Hess and Brezowsky, and the identification of drought periods has been made using the Palfai index. The spatial and temporal characteristics of drought in Romania for the 1961-1990 agricultural years have also been analyzed. The most affected regions by drought over this period were north-eastern Wallachia, south-western Oltenia, south-eastern Moldavia, and Dobrudja. It has been noticed that the drought had a general tendency to extend towards western and northern Romania. During the analyzed period, the atmospheric circulations from the western and eastern sectors over the Atlantic- European region were frequent, the western types prevailing. [ABSTRACT FROM AUTHOR]

Abstract: Accurate positioning becomes extremely important for modern application like indoor navigation and location-based services. Standalone GPS cannot meet this accuracy. In this paper a method to couple GPS and a high resolution MEMS pressure sensor is presented to improve vertical as well as horizontal (in urban canyon environment) positioning. Further, a step counter based on an accelerometer is improved with an altimeter for stair detection and automatic step length adaptation for dead reckoning inside buildings. Finally, a stand-alone system accurately tracks floor levels inside buildings, using only a pressure sensor. [Copyright &y& Elsevier]

This paper describes the development of a microwave plasma reactor for the oxidation of gaseous organic contaminants in air. The reactor was designed such that plasma could be sustained at atmospheric pressure or greater with an effluent gas flow rate of up to 2000 l/min. The oxidation of methane was chosen as the test reaction for laboratory studies. [ABSTRACT FROM AUTHOR]

This paper describes the development of a microwave plasma reactor for the oxidation of gaseous organic contaminants in air. The reactor was designed such that plasma could be sustained at atmospheric pressure or greater with an effluent gas flow rate of up to 2000 1/min. The oxidation of methane was chosen as the test reaction for laboratory studies. [ABSTRACT FROM AUTHOR]

A typical starting point in dendroclimatological research is to statistically relate tree- ring growth indices to local or regional climate variables (response function analysis). This sometimes leads to identification of links between tree growth and (often oscillatory) perturbations in atmospheric circulation, such as the El Niño-Southern Oscillation (ENSO) phenomenon. This approach relies on the researcher linking the (hopefully known) local-scale climate impacts of an oscillatory phenomenon with the response function results. A supplementary approach, advocated here, is to directly investigate relationships between tree growth and atmospheric circulation using composite mapping techniques. This paper demonstrates composite mapping, using the United Kingdom Meteorological Office gridded global monthly mean sea-level pressure (MSLP) data set and Agathis australlis (kauri) tree rings. The results show that composite mapping is a powerful tool for tree-ring research, capable of identifying atmospheric circulation characteristics associated with wide and narrow tree rings, and helping to determine the potential of tree rings for reconstructing atmospheric circulation features. Results for kauri indicate that MSLP anomaly patterns associated with wide (narrow) tree rings have strong similarities to anomaly patterns associated with El Niño (La Niña) events. Relationships are strongest for wide tree rings and for the western pole of the Southern Oscillation. The results indicate that kauri is a strong ENSO proxy, with reconstruction potential strongest for the 6 mo from September to February. [ABSTRACT FROM AUTHOR]

Copyright of Studies in Conservation is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Air Quality Standards for Particulate Matter (PM) at high altitude urban areas in different countries, must consider the pressure and temperature due to the effect that these parameters have on the breath volume. This paper shows the importance to correct Air Quality Standards for PM considering pressure and temperature at different altitudes. Specific factors were suggested to convert the information concerning PM, from local to standard conditions, and adjust the Air Quality Standards for different high altitudes cities. The correction factors ranged from: 1.03 for Santiago de Chile to 1.47 for El Alto Bolivia. Other cities in this study include: Mexico City, México; La Paz, Bolivia; Bogota, Cali and Medellin, Colombia; Quito, Ecuador and Cuzco, Peru. If these corrections are not considered, the atmospheric concentrations will be underestimated. [Copyright &y& Elsevier]