bluuebunny/crossref_metadata_2025 huggingface dataset:
Biodegradation of Picolinic Acid by Rhodococcus sp. PA18
Authors: Zhang Yanting , Ji Junbin , Xu Siqiong , Wang Hongmei , Shen Biao , He Jian , Qiu Jiguo , Chen Qing
Published: March 2019

Picolinic acid (PA), a C2-carboxylated pyridine derivative, is a significant intermediate used in industrial production. PA is considered hazardous for the environment and human health. In this study, a Gram-positive bacterium, Rhodococcus sp. PA18, which aerobically utilizes PA as a source of carbon and energy, was isolated. The strain completely degraded 100 mg/L PA within 24 h after induction and formed 6-hydroxypicolinic acid (6HPA), a major PA metabolite, which was identified using ultraviolet-visible spectroscopy, high performance liquid chromatography, and liquid chromatography/time of flight-mass spectrometry analyses. The cell-free extracts converted the PA into 6HPA when phenazine methosulfate was used as an electron acceptor. To our knowledge, this is the first report showing that PA can be metabolized by Rhodococcus. In conclusion, Rhodococcus sp. PA18 may be potentially used for the bioremediation of environments polluted with PA.
The Development of a Soft Robot Hand with Pin-Array Structure
Authors: Fu Hong , Zhang Wenzeng
Published: March 2019

This paper proposes a soft robot hand with pin-array structure and self-adaptive function, CTSA-II hand, where CTSA is the Cluster tube self-adaption. The CTSA-II hand is designed with a quite concise structure and consists of bases, a pin array, a spring array, and a membrane. When the CTSA-II hand grasps an object, the pins will slide along the trajectory to conform to the profile of the object under the reaction force applied by the object, and thus the outer membrane will form a specific shape, and then the vacuum drives the CTSA-II hand to grasp the object. Theoretical analysis shows that the CTSA-II hand can generate enough grasping force and get good stability. Moreover, the optimization of its structure is achieved by studying the effects of specific parameters. The capture experimental results of the prototype show that the CTSA-II hand can realize self-adaptive grasping of different sizes and shapes with a high degree of fit and a high success rate. A series of research experiments show the influence of various factors on the grasping force, which verifies the results of the theoretical analysis with the CTSA-II hand. Compared to the traditional robot hand, the CTSA-II hand has good crawl performance, concise structure, small volume, and easy assembly.
Optimal Design of a Tower Type SCR-deNOx Facility for a 1000 MW Coal-Fired Power Plant Based on CFD Simulation and FMT Validation
Authors: Zeng Haojun , Yuan Jingqi , Wang Jingcheng
Published: March 2019

Selective catalytic reduction (SCR) is one of the most efficient methods to reduce NOx emissions from coal-fired power plants. This paper deals with an optimal design tower type SCR-deNOx facility for a 1000 MW coal-fired power plant. Combined with computational fluid dynamics (CFD), the configuration of the baffles geometry was studied with spatial constraints. Flow field was regulated at the ammonia injection grid (AIG) with the dual aim of reducing difficulties in implementing the non-uniformed ammonia (NH3) injection strategy and achieving a more homogeneous distribution at the catalyst entrance. A flow model test (FMT) was carried out at a laboratory scale to verify the design results. The results of the flow model test are in good agreement with the computational fluid dynamics. It is indicated that small-sized baffles are recommended for installation at the upstream side of the facility as the optimal design and ability to regulate the flow field at the ammonia injection grid makes it an effective way to deal with spatial constraints. This paper provides a good reference for optimizing the tower type SCR-deNOx facilities with spatial constraints.
A Quantum Adiabatic Algorithm for Multiobjective Combinatorial Optimization
Authors: Barán Benjamín , Villagra Marcos
Published: March 2019

In this work we show how to use a quantum adiabatic algorithm to solve multiobjective optimization problems. For the first time, we demonstrate a theorem proving that the quantum adiabatic algorithm can find Pareto-optimal solutions in finite-time, provided some restrictions to the problem are met. A numerical example illustrates an application of the theorem to a well-known problem in multiobjective optimization. This result opens the door to solve multiobjective optimization problems using current technology based on quantum annealing.
A Suggested Improvement for Small Autonomous Energy System Reliability by Reducing Heat and Excess Charges
Authors: Savard Christophe , Iakovleva Emiliia V.
Published: March 2019

Devices operating in complete energy autonomy are multiplying: small fixed signaling applications or sensors often operating in a network. To ensure operation for a substantial period, for applications with difficult physical access, a means of storing electrical energy must be included in the system. The battery remains the most deployed solution. Lead-acid batteries still have a significant share of this market due to the maturity of their technology. However, even by sizing all the system elements according to the needs and the available renewable energy, some failure occurs. The battery is the weak element. It can be quickly discharged when the renewable energy source is no longer present for a while. It can also be overloaded or subjected to high temperatures, which affects its longevity. This paper presents a suggested improvement for these systems, systematically adding extra devices to reduce excess charges and heat and allowing the battery use at lower charges. The interest of this strategy is presented by comparing the number of days of system failure and the consequences for battery aging. To demonstrate the interest of the proposed improvement track, a colored Petri net is deployed to model the battery degradation parameters evolution, in order to compare them.
Big Data Management Canvas: A Reference Model for Value Creation from Data
Authors: Kaufmann Michael
Published: March 2019

Many big data projects are technology-driven and thus, expensive and inefficient. It is often unclear how to exploit existing data resources and map data, systems and analytics results to actual use cases. Existing big data reference models are mostly either technological or business-oriented in nature, but do not consequently align both aspects. To address this issue, a reference model for big data management is proposed that operationalizes value creation from big data by linking business targets with technical implementation. The purpose of this model is to provide a goal- and value-oriented framework to effectively map and plan purposeful big data systems aligned with a clear value proposition. Based on an epistemic model that conceptualizes big data management as a cognitive system, the solution space of data value creation is divided into five layers: preparation, analysis, interaction, effectuation, and intelligence. To operationalize the model, each of these layers is subdivided into corresponding business and IT aspects to create a link from use cases to technological implementation. The resulting reference model, the big data management canvas, can be applied to classify and extend existing big data applications and to derive and plan new big data solutions, visions, and strategies for future projects. To validate the model in the context of existing information systems, the paper describes three cases of big data management in existing companies.
The Relationship between Epicardial Adipose Tissue Thickness and Serum Interleukin-17a Level in Patients with Isolated Metabolic Syndrome
Authors: Demir Esra , Harmankaya Nazmiye Özlem , Kıraç Utku İrem , Açıksarı Gönül , Uygun Turgut , Özkan Hanise , Demir Bülent
Published: March 2019

In this study, it was aimed to investigate the relationship between the epicardial adipose tissue thickness (EATT) and serum IL-17A level insulin resistance in metabolic syndrome patients. This study enrolled a total of 160 subjects, of whom 80 were consecutive patients who applied to our outpatient clinic and were diagnosed with metabolic syndrome, and the other 80 were consecutive patients who were part of the control group with similar age and demographics in whom the metabolic syndrome was excluded. The metabolic syndrome diagnosis was made according to International Diabetes Federation (IDF)-2005 criteria. EATT was measured with transthoracic echocardiography (TTE) in the subjects. IL-17A serum levels were determined using the ELISA method. Fasting blood glucose, HDL, triglyceride, and fasting insulin levels were significantly higher in the metabolic syndrome group compared to the control group. In addition, the metabolic syndrome group had significantly higher high-sensitivity C-reactive protein (hs-CRP) and Homeostatic Model Assessment Insulin Resistance (HOMA-IR) levels than the control group. Similarly, serum IL-17A levels were significantly elevated in the metabolic syndrome group compared to the control group statistically (p < 0.001). As well, EATT was higher in the metabolic syndrome than the control group. Conclusion: By virtue of their proinflammatory properties, EATT and IL-17 may play an important role in the pathogenesis of the metabolic syndrome.
Optimization of Ammonia Oxidation Using Response Surface Methodology
Authors: Inger Marek , Dobrzyńska-Inger Agnieszka , Rajewski Jakub , Wilk Marcin
Published: March 2019

In this paper, the design of experiments and response surface methodology were proposed to study ammonia oxidation process. The following independent variables were selected: the reactor’s load, the temperature of reaction and the number of catalytic gauzes, whereas ammonia oxidation efficiency and N2O concentration in nitrous gases were assumed as dependent variables (response). Based on the achieved results, statistically significant mathematical models were developed which describe the effect of independent variables on the analysed responses. In case of ammonia oxidation efficiency, its achieved value depends on the reactor’s load and the number of catalytic gauzes, whereas the temperature in the studied range (870–910 °C) has no effect on this dependent variable. The concentration of nitrous oxide in nitrous gases depends on all three parameters. The developed models were used for the multi-criteria optimization with the application of desirability function. Sets of parameters were achieved for which optimization assumptions were met: maximization of ammonia oxidation efficiency and minimization of the N2O amount being formed in the reaction.
The Synthesis of Mannose-6-Phosphate Using Polyphosphate-Dependent Mannose Kinase
Authors: Zhu Wenlong , Gao Miaomiao , Chen Biqiang , Tan Tianwei , Cao Hui , Liu Luo
Published: March 2019

Mannose-6-phosphate (M6P) is involved in many metabolic pathways in life, and it has important applications in the treatment of diseases. This study explored a cost-effective enzyme catalytic synthesis method of M6P, using polyphosphate-dependent mannose kinase from Arthrobacter species. This synthesis uses polyphosphate to replace expensive ATP, and it is greener and safer than chemical synthesis. This study investigated the effects of key factors such as metal ions, temperature, and substrate addition on this enzymatic reaction, and improved the conversion efficiency. We moreover take advantage of the response surface method to explore the best catalytic conditions synthetically. The conversion was 99.17% successful under the optimal reaction conditions. After a series of optimizations, we carried out a 200 mL scale-up experiment, which proved that the method has good prospects for industrial applications.
Looking for the “Dream Catalyst” for Hydrogen Peroxide Production from Hydrogen and Oxygen
Authors: Menegazzo Federica , Signoretto Michela , Ghedini Elena , Strukul Giorgio
Published: March 2019

The reaction between hydrogen and oxygen is in principle the simplest method to form hydrogen peroxide, but it is still a “dream process”, thus needing a “dream catalyst”. The aim of this review is to analyze critically the different heterogeneous catalysts used for the direct synthesis of H2O2 trying to determine the features that the ideal or “dream catalyst” should possess. This analysis will refer specifically to the following points: (i) the choice of the metal; (ii) the metal promoters used to improve the activity and/or the selectivity; (iii) the role of different supports and their acidic properties; (iv) the addition of halide promoters to inhibit undesired side reactions; (v) the addition of other promoters; (vi) the effects of particle morphology; and (vii) the effects of different synthetic methods on catalyst morphology and performance.
Spectrophotometric Characterization of Thin Copper and Gold Films Prepared by Electron Beam Evaporation: Thickness Dependence of the Drude Damping Parameter
Authors: Stenzel Olaf , Wilbrandt Steffen , Stempfhuber Sven , Gäbler Dieter , Wolleb Sabrina-Jasmin
Published: March 2019

Copper and gold films with thicknesses between approximately 10 and 60 nm have been prepared by electron beam evaporation and characterized by spectrophotometry from the near infrared up to the near ultraviolet spectral regions. From near normal incidence transmission and reflection spectra, dispersion of optical constants have been determined by means of spectra fits utilizing a merger of the Drude model and the beta-distributed oscillator model. All spectra could be fitted in the full spectral region with a total of seven dispersion parameters. The obtained Drude damping parameters shows a clear trend to increase with decreasing film thickness. This behavior is discussed in the context of additional non-optical characterization results and turned out to be consistent with a simple mean-free path theory.
Development of Cu-Modified PVC and PU for Catalytic Generation of Nitric Oxide
Authors: Azizova Liana , Ray Santanu , Mikhalovsky Sergey , Mikhalovska Lyuba
Published: March 2019

Nitric oxide (NO) generating surfaces are potentially promising for improving haemocompatibility of blood-contacting biomaterials. In the present report, Cu-modified poly(vinyl chloride) (PVC) and polyurethane (PU) were prepared via polydopamine (pDA)-assisted chelation. The copper content on the PVC and PU modified surfaces, assessed by inductively coupled plasma - optical emission spectrometry (ICP-OES), were about 3.86 and 6.04 nmol·cm−2, respectively. The Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) data suggest that copper is attached to the polymer surface through complex formation with pDA. The cumulative leaching of copper from modified PVC and PU during the five day incubation in phosphate buffered saline (PBS), measured by inductively coupled plasma mass spectrometry (ICP-MS), was about 50.7 ppb and 48 ppb, respectively which is within its physiological level. Modified polymers were tested for their ability to catalytically generate NO by decomposing of endogenous S-nitrosothiol (GSNO). The obtained data show that Cu-modified PVC and PU exhibited the capacity to generate physiological levels of NO which could be a foundation for developing new biocompatible materials with NO-based therapeutics.
Is There a Relationship between Transepidermal Water Loss and Microbial Biodiversity on the Skin?
Authors: Wallen-Russell Christopher
Published: March 2019

As described in previous work, TEWL (transepidermal water loss) is used as an indicator of skin barrier function and health by scientists at top research institutions. However, it is known to be unreliable because many other factors determine its value, such as humidity, temperature and moisture content of the skin. In this study, to help elucidate whether it is a good indicator of the health of skin, we used bivariate linear correlation analysis and the Pearson correlation coefficient to compare values of skin microbial biodiversity with TEWL. In 2017 in our previous work, microbial biodiversity was found to currently be the only reliable indicator of skin health. Diversity was also compared with moisture content and pH, along with TEWL vs. moisture. All data was taken from the use of human participants in our previous work in 2018. Results showed no linear correlation between microbial biodiversity and TEWL rates or any of the other variables. This suggests the need for researchers to make conclusions about TEWL rates and their meaning with regards to skin function and health, with caution. Future work should consider the possibility of non-linear relationships, use larger datasets and mitigate against the effect of non-normally distributed data.
Review of Modern Techniques for the Assessment of Skin Hydration
Authors: Qassem Meha , Kyriacou Panayiotis
Published: March 2019

Skin hydration is a complex process that influences the physical and mechanical properties of skin. Various technologies have emerged over the years to assess this parameter, with the current standard being electrical probe-based instruments. Nevertheless, their inability to provide detailed information has prompted the use of sophisticated spectroscopic and imaging methodologies, which are capable of in-depth skin analysis that includes structural and composition details. Modern imaging and spectroscopic techniques have transformed skin research in the dermatological and cosmetics disciplines, and are now commonly employed in conjunction with traditional methods for comprehensive assessment of both healthy and pathological skin. This article reviews current techniques employed in measuring skin hydration, and gives an account on their principle of operation and applications in skin-related research.
Effect of Size Polydispersity on the Pitch of Nanorod Cholesterics
Authors: Wensink Henricus H.
Published: March 2019

Many nanoparticle-based chiral liquid crystals are composed of polydisperse rod-shaped particles with considerable spread in size or shape, affecting the mesoscale chiral properties in, as yet, unknown ways. Using an algebraic interpretation of Onsager-Straley theory for twisted nematics, we investigate the role of length polydispersity on the pitch of nanorod-based cholesterics with a continuous length polydispersity, and find that polydispersity enhances the twist elastic modulus, K 2 , of the cholesteric material without affecting the effective helical amplitude, K t . In addition, for the infinitely large average aspect ratios considered here, the dependence of the pitch on the overall rod concentration is completely unaffected by polydispersity. For a given concentration, the increase in twist elastic modulus (and reduction of the helical twist) may be up to 50% for strong size polydispersity, irrespective of the shape of the unimodal length distribution. We also demonstrate that the twist reduction is reinforced in bimodal distributions, obtained by doping a polydisperse cholesteric with very long rods. Finally, we identify a subtle, non-monotonic change of the pitch across the isotropic-cholesteric biphasic region.
Autonomous “Figure-8” Flights of a Quadcopter: Experimental Datasets
Authors: Gururajan Srikanth , Bai Ye
Published: March 2019

This article describes the data acquired from multiple flights of a custom-built quadcopter. The Quadcopter was programmed to fly a pre-defined “Figure-8” flight path, at a constant altitude. The data set includes flights with a varying number of waypoints (10 and 15 waypoints in each lobe of the “Figure-8”) and at two different velocities (1.5 and 2.5 m/s). The data also contains information on the output of the flight controller in terms of the Pulse Width Modulation (PWM) signals to each of the four Electronic Speed Controllers (ESC) driving the motors, the recorded outputs of the Inertial Measurement Unit (linear accelerations ax, ay, az and angular velocities p, q, r), GPS data (Latitude, Longitude, altitude, Horizontal Dilution of Precision (HDOP) and Vertical Dilution of Precision (VDOP). The data are included as Supplemental Material.
Implementing a Chaotic Cryptosystem by Performing Parallel Computing on Embedded Systems with Multiprocessors
Authors: Flores-Vergara Abraham , Inzunza-González Everardo , García-Guerrero Enrique Efren , López-Bonilla Oscar Roberto , Rodríguez-Orozco Eduardo , Hernández-Ontiveros Juan Miguel , Cárdenas-Valdez José Ricardo , Tlelo-Cuautle Esteban
Published: March 2019

Profiling and parallel computing techniques in a cluster of six embedded systems with multiprocessors are introduced herein to implement a chaotic cryptosystem for digital color images. The proposed encryption method is based on stream encryption using a pseudo-random number generator with high-precision arithmetic and data processing in parallel with collective communication. The profiling and parallel computing techniques allow discovery of the optimal number of processors that are necessary to improve the efficiency of the cryptosystem. That is, the processing speed improves the time for generating chaotic sequences and execution of the encryption algorithm. In addition, the high numerical precision reduces the digital degradation in a chaotic system and increases the security levels of the cryptosystem. The security analysis confirms that the proposed cryptosystem is secure and robust against different attacks that have been widely reported in the literature. Accordingly, we highlight that the proposed encryption method is potentially feasible to be implemented in practical applications, such as modern telecommunication devices employing multiprocessors, e.g., smart phones, tablets, and in any embedded system with multi-core hardware.
On the Diversity-Based Weighting Method for Risk Assessment and Decision-Making about Natural Hazards
Authors: Chen Pengyu
Published: March 2019

The entropy-weighting method (EWM) and variation coefficient method (VCM) are two typical diversity-based weighting methods, which are widely used in risk assessment and decision-making for natural hazards. However, for the attributes with a specific range of values (RV), the weights calculated by EWM and VCM (abbreviated as WE and WV) may be irrational. To solve this problem, a new indicator representing the dipartite degree is proposed, which is called the coefficient of dipartite degree (CDD), and the corresponding weighting method is called the dipartite coefficient method (DCM). Firstly, based on a large amount of statistical data, a comparison between the EWM and VCM is carried out. It is found that there is a strong correlation between the weights calculated by the EWM and VCM (abbreviated as WE and WV); however, in some cases the difference between WE and WV is big. Especially when the diversity of attributes is high, WE may be much larger than WV. Then, a comparison of the DCM, EWM and VCM is carried out based on two case studies. The results indicate that DCM is preferred for determining the weights of the attributes with a specific RV, and if the values of attributes are large enough, the EWM and VCM are both available. The EWM is more suitable for distinguishing the alternatives, but prudence is required when the diversity of an attribute is high. Finally, the applications of the diversity-based weighting method in natural hazards are discussed.
Learning Ecological Concepts in Secondary Schools of the Northeast of Spain
Authors: Notari Llorens Meritxell , Pardo Fabregat Francisco , Martinez-Poveda Africa , Jordan Vidal Manuel
Published: March 2019

Ecological concepts are not a recent matter; international organizations have already increased their efforts to provide better environmental education and ecological consciousness, although despite these efforts, a lack of attitudes and concepts were detected in the northeast of Spain. We evaluated the acquisition of concepts related to environmental education in the students as proposed by current legislation, as well as their relation to different parameters, such as geographical location, type of school, and gender. The result suggests that the students achieve a meaningful learning of the concepts proposed by legislation and that acquisition of this knowledge is related to gender and geographical location, but not to the type of secondary school.
Comparison of Deep Learning and Conventional Demosaicing Algorithms for Mastcam Images
Authors: Kwan Chiman , Chou Bryan , Bell III James F.
Published: March 2019

Bayer pattern filters have been used in many commercial digital cameras. In National Aeronautics and Space Administration’s (NASA) mast camera (Mastcam) imaging system, onboard the Mars Science Laboratory (MSL) rover Curiosity, a Bayer pattern filter is being used to capture the RGB (red, green, and blue) color of scenes on Mars. The Mastcam has two cameras: left and right. The right camera has three times better resolution than that of the left. It is well known that demosaicing introduces color and zipper artifacts. Here, we present a comparative study of demosaicing results using conventional and deep learning algorithms. Sixteen left and 15 right Mastcam images were used in our experiments. Due to a lack of ground truth images for Mastcam data from Mars, we compared the various algorithms using a blind image quality assessment model. It was observed that no one algorithm can work the best for all images. In particular, a deep learning-based algorithm worked the best for the right Mastcam images and a conventional algorithm achieved the best results for the left Mastcam images. Moreover, subjective evaluation of five demosaiced Mastcam images was also used to compare the various algorithms.
Implementation of Processing Functions for Autonomous Power Quality Measurement Equipment: A Performance Evaluation of CPU and FPGA-Based Embedded System
Authors: Cifredo-Chacón María-Ángeles , Perez-Peña Fernando , Quirós-Olozábal Ángel , González-de-la-Rosa Juan-José
Published: March 2019

Motivated by the effects of deregulation over power quality and the subsequent need of new types of measurements, this paper assesses different implementations of an estimate for the spectral kurtosis, considered as a low-level harmonic detection. Performance of a processor-based system is compared with a field programmable gate array (FPGA)-based solution, in order to evaluate the accuracy of this processing function for implementation in autonomous measurement equipment. The fourth-order spectrum, with applications in different fields, needs advanced digital signal processing, making it necessary to compare implementation alternatives. In order to obtain reproducible results, the implementations have been developed using common design and programming tools. Several characteristics of the implementations are compared, showing that the increasing complexity and reduced cost of the current FPGA models make the implementation of complex mathematical functions feasible. We show that FPGAs improve the processing capability of the best processor using an operating frequency 33 times lower. This fact strongly supports its implementation in hand-held instruments.
Bioconversion Pathway of CO2 in the Presence of Ethanol by Methanogenic Enrichments from Production Water of a High-Temperature Petroleum Reservoir
Authors: Yang Guang-Chao , Zhou Lei , Mbadinga Serge , Gu Ji-Dong , Mu Bo-Zhong
Published: March 2019

Transformation of CO2 in both carbon capture and storage (CCS) to biogenic methane in petroleum reservoirs is an attractive and promising strategy for not only mitigating the greenhouse impact but also facilitating energy recovery in order to meet societal needs for energy. Available sources of petroleum in the reservoirs reduction play an essential role in the biotransformation of CO2 stored in petroleum reservoirs into clean energy methane. Here, the feasibility and potential on the reduction of CO2 injected into methane as bioenergy by indigenous microorganisms residing in oilfields in the presence of the fermentative metabolite ethanol were assessed in high-temperature petroleum reservoir production water. The bio-methane production from CO2 was achieved in enrichment with ethanol as the hydrogen source by syntrophic cooperation between the fermentative bacterium Synergistetes and CO2-reducing Methanothermobacter via interspecies hydrogen transfer based upon analyses of molecular microbiology and stable carbon isotope labeling. The thermodynamic analysis shows that CO2-reducing methanogenesis and the methanogenic metabolism of ethanol are mutually beneficial at a low concentration of injected CO2 but inhibited by the high partial pressure of CO2. Our results offer a potentially valuable opportunity for clean bioenergy recovery from CCS in oilfields.
Interval Optimization-Based Unit Commitment for Deep Peak Regulation of Thermal Units
Authors: Yang Yinping , Qin Chao , Zeng Yuan , Wang Chengshan
Published: March 2019

The deep peak regulation of thermal units is an important measure for coping with significant wind power penetration. In this paper, based on interval optimization, a novel multi-objective unit commitment method is proposed considering the deep peak regulation of thermal units. In the proposed method, a thermal power cost model was developed to accurately determine the economic performance of three different peak regulation scenarios, particularly of the deep peak regulation scenario. The midpoint and width of the cost interval are simultaneously considered in the optimization process. The non-dominated sorting GA-II (NSGA-II) algorithm was incorporated into the model for a coordinated control of the midpoint and width of the obtained cost interval for further optimization. Considering that significant wind penetration results in greater nodal variations, the affine arithmetic was employed to solve nodal uncertainties, so that all system variations can be addressed. The method proposed in this paper was validated by a modified IEEE-39 bus system. The results showed that it serves as a useful tool for power dispatchers to obtain robust and economic solutions at different wind power prediction accuracies.
Systems Analysis of Biogas Production—Part I Research Design
Authors: Lindkvist Emma , Karlsson Magnus , Ivner Jenny
Published: March 2019

Striving towards a resource efficient society requires an adjustment of energy systems towards renewable options. It is also of high importance to make use of products and materials to a higher degree. Biogas production has the potential to recover nutrients and energy from organic by-products, as well as to substitute fossil fuels in the energy system. Resource efficiency relates to the economic, energy and environmental performance of the system studied. A comprehensive research design for assessment of the resource efficiency of biogas production systems is described in this paper. The research design includes the following parts: identification of cases, defining scenarios, system development, evaluation perspectives and systems analysis. The analysis is performed from three perspectives; economy, energy and environment.
Flow Boiling Heat Transfer Characteristics in Horizontal, Three-Dimensional Enhanced Tubes
Authors: Sun Zhi-Chuan , Ma Xiang , Ma Lian-Xiang , Li Wei , Kukulka David J.
Published: March 2019

An experimental investigation was conducted to explore the flow boiling heat transfer characteristics of refrigerants R134A and R410A inside a smooth tube, as well as inside two newly developed surface-enhanced tubes. The internal surface structures of the two enhanced tubes are comprised of protrusions/dimples and petal-shaped bumps/cavities. The equivalent inner diameter of all tested tubes is 11.5 mm, and the tube length is 2 m. The experimental test conditions included saturation temperatures of 6 °C and 10 °C; mass velocities ranging from 70 to 200 kg/(m2s); and heat fluxes ranging from 10 to 35 kW/m2, with inlet and outlet vapor quality of 0.2 and 0.8. It was observed that the enhanced tubes exhibit excellent flow boiling heat transfer performance. This can be attributed to the complex surface patterns of dimples and petal arrays that increase the active heat transfer area; in addition, more nucleation sites are produced, and there is also an increased interfacial turbulence. Results showed that the boiling heat transfer coefficient of the enhanced surface tubes was 1.15–1.66 times that of the smooth tubing. Also, effects of the flow pattern and saturated temperature are discussed. Finally, a comparison of several existing flow boiling heat transfer models using the data from the current study is presented.
Key Parameters of Roof Cutting of Gob-Side Entry Retaining in a Deep Inclined Thick Coal Seam with Hard Roof
Authors: Hu Jinzhu , He Manchao , Wang Jiong , Ma Zimin , Wang Yajun , Zhang Xingyu
Published: March 2019

Gob-side entry retaining by roof cutting (GERRC) employed in a deep inclined thick coal seam (DITCS) can not only increase economic benefits and coal recovery, but also optimize surrounding rock structure. In accordance with the principles of GERRC, the technology of GERRC in DITCS is introduced and a roof-cutting mechanical model of GERRC is proposed to determine the key parameters of the depth and angle of RC. The results show that the greater the RC angle, the easier the caving of the goaf roof, but the length of cantilever beam increases. The depth of RC should account for the dip angle of the coal seam when the angle is above 20°. Increasing the coal seam dip angle could reduce the volume of rock falling of the goaf roof, but increase the filling height of the upper gangue to slide down. According to numerical model analysis of the stress and displacement of surrounding rock at different depths and angles of RC, when the depth of RC increased from 9 m to 13 m, the distance between the stress concentration zone and the coal side is increased. When the angle of RC increased from 0° to 20°, the value of roof separation is decreased. GERRC was applied in a DITCS with 11 m depth and 20° RC angle, and the field-measured data verified the conclusions of the numerical model.
Optimal Operation Strategies into Deregulated Markets for 50 MWe Parabolic Trough Solar Thermal Power Plants with Thermal Storage
Authors: Llamas Jorge , Bullejos David , Ruiz de Adana Manuel
Published: March 2019

The evolution of electric generation systems, according to relevant legislation, allows for the parallel evolution of the installed power capacity of renewable resources with the development of technologies for renewable resources, therefore optimizing the choice of energy mix from renewable resources by prioritizing the implementation of concentrating solar thermal plants. Thanks to their great potential, parabolic trough solar thermal power plants have become the most widely spread type of electricity generation by renewable solar energy. Nonetheless, the operation of the plant is not unique; it must be adapted to the parameters of solar radiation and market behavior for each specific location. This work focuses on the search for the optimal strategies of operation by a mathematical model of a 50 MWe parabolic trough thermal power plant with thermal storage. The analysis of the different ways of operation throughout a whole year, including model verification via a currently operating plant, provides meaningful insights into the electricity generated. Focused to work under non-regulated electricity markets to adjust this type of technology to the European directives, the presented model of optimization allows for the adaptation of the curve of generation to the network demands and market prices, rising the profitability of the power plant. Thus, related to solar resources and market price, the economic benefit derived from the electricity production improves between 5.17% and 7.79%.
Research on Distribution and Shielding of Spatial Magnetic Field of a DC Air Core Smoothing Reactor
Authors: Yang Jiameng , Zhang Wenfang , Zou Liang , Wang Yali , Sun Youliang , Feng Yingchun
Published: March 2019

With the rapid development of ultra-high-voltage direct current (UHVDC) transmission, air core smoothing reactors have become the main source of electromagnetic contamination in converter substations. The actual magnetic field distribution was obtained by measuring the magnetic induction intensity of the polar busbar smoothing reactor under full load operation condition of the Jiaodong ±660 kV converter substation. A method combined with the measured data to eliminate the influence of the geomagnetic field is proposed. The magnetic field distribution model of the smoothing reactor is established and the rationality and validity of the model for magnetic field distribution is verified. Some magnetic shielding measures are proposed and their effectiveness is verified by simulation and small-scale experiments.
Differences in the Climate-Growth Relationship of Scots Pine: A Case Study from Poland and Hungary
Authors: Misi Dávid , Puchałka Radosław , Pearson Charlotte , Robertson Iain , Koprowski Marcin
Published: March 2019

Scots pine is an adaptable and prevalent European tree species that grows naturally throughout Europe and has been planted in a wide range of environments. Previous studies have indicated that climatic variables affect tree-ring growth patterns in this species, but it is also possible that certain aspects of the growth environment moderate this response. In order to understand the potential impact a shifting climate has on this important species, this study compared the growth response of two populations of Scots pine. Trees from similar bioclimatic regions in Hungary and Poland were compared using the hypothesis that differences in the association between climate and growth would be reflected by the degree of tree-ring width variation. We also wanted to know how changing climatic conditions influenced the temporal stability of the climate–growth signal in the most important periods for tree growth. Clear similarities in the effect of temperature and precipitation on tree-ring width variation were found between the two sites, but there were also some interesting differences. In the late winter to early spring period both populations reacted to warming with a decreasing association with temperature. Summer precipitation was shown to be the dominant factor in controlling ring-width. A decreasing trend in summer precipitation values at both Hungarian and Polish sites resulted in a weakening in correspondence for the Hungarian trees, while the Polish trees showed a significant increase in correlation with summer precipitation. The results indicated that changes in climate influenced the studied trees in different ways which has implications for the future balance of Scots pine growth in Europe.
Spatiotemporal Ozone Level Variation in Urban Forests in Shenzhen, China
Authors: Duan Wenjun , Wang Cheng , Pei Nancai , Zhang Chang , Gu Lin , Jiang Shasha , Hao Zezhou , Xu Xinhui
Published: March 2019

This study is among the first to investigate ozone levels in urban forests in China. It establishes that urban forest air quality in Yuanshan Forest Park (Shenzhen) is suitable for recreational activities and identifies spatial, seasonal, and diurnal O3 patterns and relationships with micrometeorological parameters, suggesting the possibility of manipulating relevant forest characteristics to reduce Surface ozone (O3) levels. An understanding of O3 levels of urban forest environments is needed to assess potential effects on human health and recreational activities. Such studies in China are scarce. This study investigated urban forest O3 levels to improve understanding and support residents engaging in forest recreational activities. We monitored O3 levels in 2015–2016 for three urban forests representing common habitats (foothill, valley, and ridge) in Yuanshan Forest Park and for an adjacent square. The overall mean daily and daily maximum 8 h mean (MDA8) O3 concentrations were highest for the ridge forest and lowest for the valley forest. Each forest’s O3 concentrations were highest in summer. Diurnally, forest O3 concentrations peaked between 13:00 and 17:00 and reached a minimum between 03:00 and 09:00. The correlation between forest O3 concentrations and air temperature (AT) was strongly positive in summer and autumn but negative in spring. In each season, O3 concentration was negatively correlated with relative humidity (RH). No MDA8 or hourly O3 concentrations in the forests exceeded National Ambient Air Quality Standard Grade I thresholds (100 and 160 μg m−3, respectively). O3 accumulation is present in ridge urban forest in all seasons. Foothill and valley urban forests have better air quality than ridge forestation. Urban forest air quality is better in spring and autumn than in summer and is better from night-time to early morning than from noon to afternoon.
Influence of Rainfall on Canopy Interception in Mixed Broad-Leaved—Korean Pine Forest in Xiaoxing’an Mountains, Northeastern China
Authors: Sheng Houcai , Cai Tijiu
Published: March 2019

The mixed forest of broad-leaved and Korean pine is the dominant type in the Xiaoxing’an and Changbai Mountains of China. However, few studies have been done on its canopy interception of rainfall. In this study, rainfall amount, rainfall intensity, and canopy interception were monitored during the growing seasons in 2010 and 2011. The results showed that cumulative canopy interception of rainfall was 22.0% and 21.9% in 2010 and 2011, respectively. However, the canopy interception of rainfall varied with rainfall events from 6.6% to 82.7% in 2010, and from 8.7% to 80.2% in 2011. The relationship between rainfall amount and the ratio of canopy interception to rainfall amount could be described by a power function (P < 0.01), i.e., the canopy interception decreased with the increasing rainfall amount and intensity. These results indicate that the rainfall amount and intensity were important factors for estimating the canopy interception of the studied forest type.
Actuator Materials: Review on Recent Advances and Future Outlook for Smart Textiles
Authors: Kongahage Dharshika , Foroughi Javad
Published: March 2019

Smart textiles based on actuator materials are of practical interest, but few types have been commercially exploited. The challenge for researchers has been to bring the concept out of the laboratory by working out how to build these smart materials on an industrial scale and permanently incorporate them into textiles. Smart textiles are considered as the next frontline for electronics. Recent developments in advance technologies have led to the appearance of wearable electronics by fabricating, miniaturizing and embedding flexible conductive materials into textiles. The combination of textiles and smart materials have contributed to the development of new capabilities in fabrics with the potential to change how athletes, patients, soldiers, first responders, and everyday consumers interact with their clothes and other textile products. Actuating textiles in particular, have the potential to provide a breakthrough to the area of smart textiles in many ways. The incorporation of actuating materials in to textiles is a striking approach as a small change in material anisotropy properties can be converted into significant performance enhancements, due to the densely interconnected structures. Herein, the most recent advances in smart materials based on actuating textiles are reviewed. The use of novel emerging twisted synthetic yarns, conducting polymers, hybrid carbon nanotube and spandex yarn actuators, as well as most of the cutting–edge polymeric actuators which are deployed as smart textiles are discussed.
Preventive Effect of Lactobacillus fermentum CQPC08 on 4-Nitroquineline-1-Oxide Induced Tongue Cancer in C57BL/6 Mice
Authors: Liu Bihui , Zhang Jing , Yi Ruokun , Zhou Xianrong , Long Xingyao , Pan Yanni , Zhao Xin
Published: March 2019

Lactobacillus fermentum CQPC08 (LF-CQPC08) is a newly discovered strain of bacteria isolated and identified from traditional pickled vegetables in Sichuan, China. We used 4-nitroquinoline 1-oxide to establish an experimental tongue cancer mouse model to evaluate the preventive effect of LF-CQPC08 on tongue cancer in vivo. Lactobacillus delbruechii subsp. bulgaricus, is a common commercial strain and is used as a positive control to compare the effect with LF-CQPC08. The preventive strength and mechanism of LF-CQPC08 on tongue cancer were determined by measuring the biochemical indicators in mouse serum and tissues. Our results showed LF-CQPC08 inhibits the decline of splenic index, thymus index, percentage of phagocytic macrophages, and phagocytic index effectively. LF-CQPC08 also increased levels of mouse serum granulocyte-colony stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), immunoglobulin (Ig)G, IgM levels of serum interleukin (IL)-4, IL-12, tumor necrosis factor-alpha, and interferon-gamma levels, thereby inhibiting the decline in immunity caused by tongue cancer. It also increased the activity levels of superoxide dismutase and glutathione peroxidase and decreased the levels of malondialdehyde in the tissues of the tongue cancer mouse model, thereby suppressing the oxidative stress damage in the tissue caused by tongue cancer. Through quantitative PCR, LF-CQPC08 upregulated the mRNA expression of nuclear factor-erythroid 2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1), glutathione-S-transferases-π (GST-π), and Bcl-2-associated X protein (Bax), and downregulated the mRNA expression of p53, p63, p73, phosphatase and tensin homolog (PTEN), B-cell lymphoma 2 (Bcl-2) and B-cell lymphoma-extra large (Bcl-xL) in the tongue tissues of the tongue cancer mouse. These results indicated that LF-CQPC08 reduced the influence of tongue cancer on the immune system and oxidative balance and improved the immunity and enhanced antioxidant capacity of the mouse model, thereby preventing tongue cancer. LF-CQPC08 could be used as a microbial resource with a preventive effect on tongue cancer.
Environmental Catastrophe as Morphogenesis: Inhuman Transformations in Ballard’s Climate Novels
Authors: Ingwersen Moritz
Published: March 2019

This paper offers a discussion of J. G. Ballard’s first four novels, The Wind From Nowhere (1962), The Drowned World (1962), The Drought (1965), and The Crystal World (1966) that centers on their portrayal of environmental transformation. Drawing on revised conceptualizations of the second law of thermodynamics and recent materialist scholarship, I illustrate how Ballard invokes material transformations that are ambivalently coded as terminal stasis and morphogenesis. In anticipations of the paradigm of the Anthropocene and ecocritical approaches to global climate change, Ballard’s novels re-embed the human in an ecology of inhuman forces and modes of self-organization that radically challenge entrenched ontological divisions and systemic boundaries. Particular attention is paid to the ways in which emergent structures, such as hurricanes and crystals identify his landscapes as dissipative systems far from equilibrium and rife with potential for the spontaneous generation of form. This resonance with scientific frameworks reveals itself in poetic registers that parallelize metaphors of life and death, and hinge on an estrangement of not only landscape, but also temporality, thus literalizing what it might mean to understand the human as a geological subject in the age of the Anthropocene.