bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of yeast in the wastewater treatment
Authors: Wang Yan , Qiu Liping , Hu Mengfei
Published: September 2018

Yeast, as a very valuable microbial resource, has a good enzyme system in the body and can adapt to a variety of special environments. Therefore, it plays an important role in the biological treatment of wastewater. The classification and basic characteristics of yeast were introduced, and the application of yeast in the field of wastewater treatment such as high concentration organic wastewater, heavy metal ion wastewater and domestic sewage were summarized. With the mature of yeast technology and the development of science and technology, more techniques such as gene engineering and immobilization technology will be used to treat with yeast, so that it will have a wider application prospect in wastewater treatment.
Application of Ceramic Membrane in Water and Wastewater Treatment
Authors: LIN Feng , ZHANG Shoubin , MA Guoqiang , QIU Liping , SUN Huajun
Published: September 2018

In recent years, ceramic membranes have been widely used in the field of water and wastewater treatment by virtue of their advantages over conventional water treatment technologies. In this article, definition, classification and characteristics of ceramic membrane were introduced firstly. And then the application of ceramic membrane technology used in various fields of water and wastewater treatment was highlighted. Finally, several opinions on the development prospects of ceramic membrane technology were raised.
Application of Cyclone Gas Cap Water Washing Device in Ultra Clean Discharge Treatment Technology of Exhaust Gas
Authors: Hu Jingling , Yang Senlin , Zhong Lu , Yang Yingxin , Hu Xiaotu , Xue Xueliang
Published: September 2018

Exhaust gas treatment device of coal fired boiler has been upgraded with ultra clean discharge treatment technology, and the new cyclone gas cap washing device is applied in the second half of the desulfurzing tower systm.This new water scrubbing tray system is composed with water sprays, ceramic packing, cyclone gas cap and independent water tank, which is proven by field tests, has exceling effect on exhaust gas treatment, and can decrease concentration of aerosol in exhaust gas to below 5mg/Nm3 which is lower than the state discharge standard.
A Modified Activated Sludge Model No.3 (ASM3) for Membrane Bioreactor (MBR) with an Emphasis for Solids Hydrolysis
Authors: Jiang Xinyue , Xu Bin
Published: September 2018

The previously assumed “inert” organics measured by respirometric method has been reported to be hydrolysable under long sludge retention time (SRT) configuration such as membrane bioreactor(MBR). The sludge production under long SRT has also shown to be lower than the standard activated sludge model (ASM) prediction. The hydrolysis of “inert” organics can provide the extra carbon source for denitrification. The current modeling approach has not yet included this aspect. In this study, a modified ASM3 was developed to account for the hydrolysis of “inert” organics and subsequent effect on the denitrification process under long SRT.
Influence of plantation of a shelter-belt on component of organic carbon in the Taklimakan desert over last decade
Authors: Zhengzhong Jin , Yingju Wang , Jiaqiang Lei
Published: September 2018

The soils were collected from the Taklimakan Desert Highway shelter-belt with different planting years in Xinjiang, northwest of China. The soil organic carbon stork (SOCstork) in each layers. By chemical and physical pretreatment, we measured four carbon passive organic carbons, i.e., microaggregates organic carbon(OCMIA), humus organic carbon (OCHS), carbon resistance to oxidation (OCNaClO) and acid hydrolysis (OCHCl). The results showed that the OC and SOCstorkwas decreased with soil depth mainly in 0-50 cm. The artificial vegetation have more influence on TOC, OCMIAand OCHSthan OCNaClOand OCHCl. The Tamarix chinensis shelter-belt is the most helpful for carbon sequestration in sandy soil and stabilization in surface layer than Calligonum mongolicunl and Haloxylon ammodendron.
Study on purification effect of infiltration materials to pavement runoff pollution
Authors: Xu Xueling , Kang Aihong , Lu Zhingping , lou Keke , Kou Changjiang
Published: September 2018

The concentrations of pollutants in pavement runoff are higher than those in other surface runoff normally, which causes serious problems in protecting the environment of receiving rivers and soils. According to the concept of low impact development (LID), a pavement runoff pollution control measure was developed by using infiltration structure. In order to infiltration structure play a superior role in the control of pavement runoff pollution, purification capacity of four typical infiltration materials was tested. Then, long-term purification efficiency of infiltration materials was explored to suspended solids. Besides, microscopic observation was performed on infiltration materials. Results indicated that purification effects of infiltration materials were significantly different. The purification process can be divided into three stages, which ware "rapid upgrading ", "slow upgrading " and "slow reduction ". Finally, Infiltration materials mainly have two modes to intercept runoff pollutants, which were pore adsorption and mechanical interception of the gap between materials.
Research on Humanization Design of Green Building Based on Big Data
Authors: Fang Niu
Published: September 2018

Now people life is becoming better and better, the demand for life also gradually increases. Based on the current situation of China's rising economic strength and large population base, the demand for construction has been expanded. Therefore, the construction industry has brought a lot of pollution and energy consumption. The solution to this problem is to insist on sustainable development, namely green building design. To carry on green design and better safeguard the purpose of the green design and humanized service, based on the powerful weapon Internet, we bring China's powerful weapon for China developed Internet, which is big data.
Analysis of Factors Influencing the Coordinated Development of New Urbanization with Green and Low Carbon under the Ecological Perspective - Taking Heilongjiang Province as an Example
Authors: Li Youjun , Li Wei
Published: September 2018

Under the ecological perspective, the new type of urbanization, green and low-carbon coordinated development is a powerful engine for economic development. Based on the analysis of the existing results of the new urbanization green development and low-carbon development factors, a new index system of influencing factors for the coordinated development of green and low-carbon urbanization was constructed. And then concludes the results of the analysis by using the relevant statistical data of Heilongjiang Province from 2007 to 2017, using the principal component analysis method and using SPSS statistical software. Finally, puts forward some relevant countermeasures and suggestions on scientific and technological innovation, the industrial structure and cultural education, etc.
A review work of urban ecosystem services and their interactions with dweller demand factors in modern China
Authors: Zhao Liang
Published: September 2018

Nowadays, various urban ecosystem services (UES) provided by urban green infrastructure (UGI) have been the concern of scholars worldwide. And as China being recognized as a living laboratory in sustainable studies, concerns toward UES provided by UGI and factors of urban dweller demands is definitely required. However, for related reviews and special discussions are lacking until now, this study calculated the types of UES and demand concerns with a collection of 54 Chinese and 51 English articles in UES studies, 162 Chinese and 26 English articles in urban dweller research. In addition, with detailed discussions through spatial distributions, perspectives, and methodologies, comprehensive analyses were conducted and unique features were summarized to back up other nations or situations worldwide.
The effects of environmental regulation and technological innovation on green growth: A theoretical analysis
Authors: Xu Xuefei , Wang Lili , Chen Shang
Published: September 2018

As green growth has attracted a great deal of attention due to the growing concern about the degradation of natural resources and environmental pollution in China, the questions of how to achieve it and which factors drive green growth have become hot topics. Environmental regulation and technological innovation are two main fulcrums in the realization of green growth. However, there is lacking a deeper understanding of the impact of environmental regulation and technological innovation on green growth in a methodological framework. Accordingly, this paper attempts to analyze how these factors affect the implementation of green growth in a model. The findings reveal that (1) in the short term, environmental regulation has inhibited green growth, but has a positive impact on green growth in the long run, (2) technological innovation plays a positive role in green growth improvement, and (3) the causality chain among regulation, technological innovation, and green growth is a typical mediation model. Technological innovation plays an important mediation role in the causal chain. This study not only enriches and deepens theories on green growth, but also successfully implements green growth practices and improve their performance.
How polyethene came about
Authors: Michels Thijs
Published: September 2018

Polyethene (PE) is the world’s most common polymer, with applications from low-cost to extreme-performance products. Its origin, as low-density LDPE, can be traced back to a long tradition in fundamental thermodynamics and to a liberal international universityindustry collaboration. A first application became of world-wide significance 75 years ago.
Persistent Homology applied to location problems
Authors: Bennis Driss , Gharib Fouad , Lebbar Ghita
Published: September 2018

Different approaches to solve location problems in transport and logistics have been developed in the literature. This article introduces a new approach using the concept of persistent homology which has been proved to be an efficient method in topological data analysis; and has been served as an alternative new tool in many and various research areas such as image processing, material science and biological systems. Precisely, inspired by the notions of the first homology groups and the persistent homology which mainly describe the behaviour of connectivity relation between elements during a filtration of specific topological spaces; we develop a new method and approach for the treatment of facility location–network design problems.
Support Vector Machines for Improving Vehicle Localization in Urban Canyons
Authors: Bassma Guermah , Hassan El Ghazi , Tayeb Sadiki
Published: September 2018

Since the middle ages, the need to identify the vehicles position in their local environment has always been a necessity and a challenge. Today, GNSS-based positioning systems have penetrated several field, such as land transport, emergency systems and civil aviation requiring high positioning accuracy. However, the performances of GNSS-based systems can be degraded in harsh environment due to non-line-of-sight (NLOS), Multipath and masking effects. In this paper, for improving vehicle localization in urban canyons, we address a very challenging problem related to GNSS signal reception state detection (LOS, NLOS or Multipath). A SVMbased system for GNSS Multipath detection using the fusion of information provided by two GNSS antennas is proposed. In this work, we aim to explore the potential of machine learning, and more precisely, Support Vector Machines (SVM) to identify GNSS signals reception state. The SVM-based system developed in this work has used the C/N0 of signals provided by RHCP and LHCP antennas, and satellite elevation as classification criteria. The training data set is constructed by several experimental studies done in real environments, Calais, France . Furthermore, four SVM kernel functions are tested, namely, Linear, Gaussian, Cubic and Quadratic.

A GNSS signal reception state detection by applying the proposed SVM-based classifier is demonstrated on real GPS signals, and the efficiency of the system is shown. We obtain empirically an accuracy of signal detection about 93%.
A Novel Hybrid Approach for Optimizing the Localization of Wireless Sensor Networks
Authors: Lakhbab Halima
Published: September 2018

Wireless sensor networks are used for monitoring the environment and controlling the physical environment. Information gathered by the sensors is only useful if the positions of the sensors are known. One of the solutions for this problem is Global Positioning System (GPS). However, this approach is prohibitively costly; both in terms of hardware and power requirements. Localization is defined as finding the physical coordinates of a group of nodes. Localization is classified as an unconstrained optimization problem. In this work, we propose a new algorithm to tackle the problem of localization; the algorithm is based on a hybridization of Particle Swarm Optimization (PSO) and Simulated Annealing (SA). Simulation results are given to illustrate the robustness and efficiency of the presented algorithm.
Analysis of the transport - precariousness relationship in the peripheral areas of Casablanca
Authors: Hbiak Ishak , Adidi Abdelaziz , El Brirch El Hassan , Nicolas Jean-Pierre
Published: September 2018

Casablanca is the largest metropolis in Morocco and the Maghreb and one of the largest cities in Africa. However, like most cities in developing countries, it faces major problems in terms of planning and transport. The problems in transport are of different types and affect all areas of the city, especially the peripheral areas of Casablanca, which are experiencing significant difficulties in terms of accessibility, knowing that these areas are the most precarious. The aim of this work is to confront on the one hand the global GIS analysis of the transport supply and its relation with the precariousness of the populations, and on the other hand the real problem of access to economic opportunities because of the exorbitant costs of public transport in relation to the income of these peripheral populations, taking into account the case of the peripheral city of Errahma. This second analysis was carried out through a field survey, on the area of the new city of Errahma. Initial analysis of this work has confirmed the existence of a very strong relationship between transport supply, loss of economic opportunity and precariousness in these peripheral areas.
Wireless Sensors Network for Traffic surveillance and management in Smart Cities
Authors: El Mrini Anass , Ghacham Amrani Abdellatif
Published: September 2018

The efficiency of a city’s own transportation system heavily influences its economic growth due to the increasing need to transport labour force, consumers and cargo. The use of the latest technologies to solve traffic problems is the main theme of ITS “Intelligent transportation system”, several solutions are already in use in many cities around the world and it is an indispensable part of the smart cities project. Our research focuses on developing a solution to manage road traffic in a smart city environment by utilizing wireless sensor network as medium to surveille the traffic. In this paper, we propose a set of countermeasures to avoid congestion and improve the flow of the traffic. The proposed countermeasures were simulated, and the results showed that our plan reduced the traffic congestion, minimized gases emission and increased fuel usage efficiency.
Study on the Cutting Efficiency of High-Speed Band Saw Blade by Taylor Tool Life and Fractal Equations
Authors: Wu Sung-Hua , Huang Ming-Shyan , Jhou Cheng-En , Wei Chin-Chung
Published: September 2018

The study proposed the chip formation steady-state model and cutting efficiency model for multi-cutters by Taylor tool life and fractal equation according to uniform chip thickness in high-speed band sawing process. Furthermore, a kind of new hook-tooth can be successfully applied on continuously uniformed chip formation in order to raise the production precision. The study developed MDOF cutting dynamics, which can be applied on multi-cutting process by Taylor tool life and fractal equations. Factors of affecting band-sawing included the cutting force, the cutting geometry, the cutting heat, the local stress-strain and the chip thickness formation uniformity. These factors had an important influence on tool wear, surface roughness, production precision and cutting efficiency in high-speed sawing process. The simulated results shown that, the wear resistance property is better at coating TiN 0.6 μm. In high-speed cutting process, the cutting improvement rate can be increased at least 13%. While the hook-tooth cutting speed achieved 120 m/min, comparing with non-coating cutting tooth, coating 0.6μm coating-layer can make the temperature decreased, obviously.
Evaluation of the Power Output Performance Improvement of a 2 MW Wind Turbine
Authors: Liu Jui-Hung , Chen Jien-Chen , Lai Wen-Jhen , Su Wei-Niam
Published: September 2018

This paper shows the possibility of the output improvement to a large wind turbine, so the operator can earn more and thus reduce the overall cost of energy. For a modern wind turbine certificated by IEC or DNV-GL guidelines, a 20 years design lifetime is a base line. However, the efficiency of the turbine will degrade after 8 or 9 years’ operating. Some components, especially the turning blade, the efficiency may vary due to the surface condition change. Meanwhile, the controller technology may also have been improved after years. So, the turbine can regain its original output or even have a better output performance through some adjustments. In this paper, a 2 MW wind turbine with different design and operating parameters like blade efficiency, wind direction alignment, high/low wind control strategy has been evaluated, then with the software DNV-GL BLADED simulation, to calculate the output differences and availability of the turbine. The result shown that a 3~5% yield annually can be obtained for each improved parameter in a 9 m/s mean wind speed situation.
Study on Machine Learning Based Intelligent Defect Detection System
Authors: Huang Chung-Chi , Lin Xin-Pu
Published: September 2018

In the paper, it is proposed to develop a machine learning based intelligent defect detection system for metal products. The common machine vision system has the surface (stain, shallow pit, shallow tumor, scratches, Edge defects, pattern defects) detection, or for the processing of the size, diameter, diameter, eccentricity, height, thickness and other parts of the non-contact numerical parameters of detection. Considering the quality of the work piece and the defects of the standard, so for the quality of customized testing requirements, the study is the development of machine vision and machine learning metal products defect detection system, mainly composed of three procedures: Image preprocessing, training procedures and testing procedures. The system architecture consists of three parts: (1) Image preprocessing: we first use the machine vision. OPENCV to carry out the image pre-processing part of the product before the detection. (2) Training procedures: The algorithm of the machine learning includes the convolution neural network (CNN), chunk-max pooling is used to train the program, and the generative adversarial network (GAN) based architecture is used to solve the problem of small datasets for surface defects. (3) Testing procedures：The Python language is used to write the program and implement the testing procedures with the GPU-Based embedded hardware In industries, collecting training dataset is usually costly and related methods are highly dataset-dependent. So most companies cannot provide Big-data to be analyzed or applied. By the experimental results, the recognition accuracy can be obviously improved as increasing data augmentation by GAN-Based samples maker. Manual inspection is labor intensive, costly and less in efficiency. Therefore, this study will contribute to technological innovation, industry, national development and other applications. (1) The use of intelligent machine learning technology will make the industry 4.0 technology more sophisticated. (2) It will make the development of equipment industry be better by the machine learning applications. (3) It will increase the economics and productivity of countries for the aging of the population by machine learning.
Application of a Hybrid Method for Power System Frequency Estimation with a 0.2-second Sampled Period
Authors: Lee Chih-Hung , Tsai Men-Shen
Published: September 2018

The signal processing technique is one of the principal tools for diagnosing power quality (PQ) issues in electrical power systems. The Discrete Fourier Transform (DFT) is a frequency analysis technique used to process power system signals and identify PQ problems. However, the DFT algorithm may lead to spectral leakage and picket-fence effect problems for asynchronously sampled signals that contain harmonic, inter-harmonic, and flicker components. To resolve this shortcoming, a hybrid method for frequency estimation based on a second-level DFT approach and a frequency-domain interpolation algorithm to obtain the accurate fundamental frequency of a power system is proposed in this paper. This method uses a second-level DFT to compute the cosine and sine parts for the fundamental frequency components of the acquired signals. Then, a frequency-domain interpolation approach is adopted to determine the amplitude ratio for the cosine and sine parts of the system’s fundamental frequency. A set of mixed signals with harmonic, inter-harmonic, and flicker components with the fundamental frequency deviation is used. The evaluation results demonstrate the superiority of the new method over other approaches for assessing asynchronously sampled signals contaminated with noise, harmonic, inter-harmonic, and flicker components.
Designing a video laryngoscope imaging system with a 7mm blade for neonatal patients
Authors: Hsu Ming-Ying , Hsiao Wen-Tse , Chang Han-Chao
Published: September 2018

When a newborn infant has been pushed from the birth canal due to ventilation failure while using a resuscitation mask, the doctor must implement infant intubation and other emergency steps to keep the baby alive. However, due to the excessively small mouth area of a newborn or premature infant, the doctors are unable to view the glottis entrance, which can lead to either a failed intubation or longer intubation time, thereby resulting in either a drop in oxygen levels or a rise in intrathoracic pressure. Although the normal video laryngoscope with a 12mm metal blade certainly improves this type of difficult intubation, nevertheless, doctors often complain that the depth of field (DOF) is insufficient and the width of the blade is too wide when performing intubation on neonatal patients. Therefore, this study aims to develop two modules of infant’s video laryngoscope, an ultra-thin 7mm metal blade and an optical imaging system, the core technology of which includes an optical design of a 2.5mm lens and verifications of imaging quality. In order to allow physicians to determine the infant’s airway position immediately and to avoid the binocular disparity from a physician while giving intubation, this study has simulated the optical properties of monolithic lenses while designing the imaging system, allowing the doctor to have a clearer and undistorted image within the field of view.
Smart Learning of Porn Fake News in the Family-Friendly Filters
Authors: Jow Meiling , Shiao Yaojung
Published: September 2018

The proliferation of fake news on Facebook and Google has been a hot-button topic after the 2016 US presidential election. Fake news phenomenon is not limited in the political sphere. The porn industries have been using affiliate marketers to send fake news to reach more consumers, even children. Easy availability of pornography for children on the internet has been an issue. In US, the average age of exposure to porn is 11 to 12. Frequent exposure to pornography may lead to normalization of harmful behaviors. Starting late 2013, internet service providers in Britain made “family-friendly filters,” which block X-rated websites, the default for customers, because kids are exposed to pornography at a young age. Google banned pornographic ads from its search engine from July 2014. Prostitution and escort services extend its market despite these efforts for the sake of the upsurge porn fake news. Porn fake news is produced purposefully to click, share, react, and comment. To mitigate the damage caused by porn fake news, designing a fully automated fake news detector is currently infeasible, because the problem at hand is too complex for technology alone. Even the subproblem of defining the criteria under which to classify news as “fake” creates ambiguity that requires human judgment. The ability to determine whether an article is real or fake requires more than just information about the article; it requires an understanding of cultural factors, for example “tea” maybe used by prostitution and escort services in Taiwan. This paper suggests one way to use artificial intelligence and human judgment to make it more valid to quarantine porn fake news.
Effect of the thickness reduction of specimens on the limit strains in thermomechanical tensile tests for hot-stamping studies
Authors: Lane Connor , Shao Zhutao , Zheng Kailun , Lin Jianguo
Published: September 2018

Sheet metal formability under hot stamping conditions has been evaluated using a novel planar testing system developed previously, being used within a Gleeble machine. Nevertheless, the specimen design with the central recess was not standardised, and the thickness reduction was not applied to the dog-bone type of specimen for testing at the uniaxial straining state. In this paper, effect of thickness reduction of dog-bone specimens on limit strain measurement under hot stamping conditions is investigated, and two types of dog-bone specimens without and with central recess are presented. Thermomechanical uniaxial tensile tests were performed at various deformation temperatures and strain rates, ranging from 370–510 °C and 0.01–1/s, respectively, by using the developed biaxial testing system in the Gleeble. The distributions of temperature and axial strain along gauge region of the two types of specimen were measured and compared. The specimen with consistent thickness had a better uniformity of temperature and strain distributions, compared to that with thickenss reduction. Forming limits for both types of specimen were also determined using the section-based international standard method. It is found that the accuracy of the calculation of forming limits based on the use of specimen with thickness reduction was highly dependent on the selection of the stage of the deformation of the specimen.
Debye length and electric potential in magnetized nonextensive plasma
Authors: Hatami M. M. , Tribeche M. , Mamun A. A.
Published: September 2018

The modification of Debye length and electric potential due to the combined effects of nonextensive distribution of particles in an electron-ion plasma system, ratio of electron temperature to ion temperature, and external static magnetic field is theoretically examined. The expression for the modified Debye length is derived by solving Poisson's equation. The effects of different plasma parameters (viz., nonextensive parameters for electron and ion species, ratio of electron temperature to ion temperature, and external static magnetic field) on the modified expressions for the Debye length and electric potential are pinpointed.
Tutorial: Broadband fiber-wireless integration for 5G+ communication
Authors: Yu Jianjun , Li Xinying , Zhou Wen
Published: September 2018

The increased bandwidth demand has motivated the exploration of fiber-wireless integration (FWI) for future broadband 5G+ cellular communication networks. FWI offers ultra-wideband (UWB) wireless delivery with low interference, which will be prospective for 5G/5G+ mobile communication wireless access, military application, disaster emergency communication, broadband communication at home, and so on. As an effective carrier, millimeter-wave (mm-wave) frequencies between 30 GHz and 300 GHz are a new frontier for FWI that offers the promise of orders of magnitude greater bandwidths. In this paper, we summarize all kinds of enabling technologies for FWI, including the photonic vector mm-wave generation scheme, the integration of various multi-dimensional multiplexing techniques, radio-frequency-transparent (RF-transparent) photonic demodulation technology for fiber-wireless-fiber network, and low-complexity high-efficiency digital signal processing (DSP). Based on DSP for UWB high-spectrum-efficiency signal coherent detection, we have made great progress in the field of the mm-wave-band (from Q- to D-band) broadband signal generation and long-distance transmission. These experimental results show that FWI with large-capacity, long-distance, and high-spectrum-efficiency has important scientific and practical significance for the development of the future 5G+ wireless communication.
Development of low phase noise microwave frequency synthesizers for reducing Dick effect of Cs fountain clocks
Authors: Li Wenbing , Du Yuanbo , Li Hui , Lu Zehuang
Published: September 2018

The Dick effect is one of the main factors limiting the short-term frequency stability of Cs fountain clocks, which is especially decided by the phase noise of the local oscillator at smaller offset frequency. Here we report on the development of a 9.192 GHz microwave frequency synthesizer with low phase noise to be used as the local oscillator for Cs fountain clocks. The synthesizer is based on frequency multiplication and synthesis from an ultra-low phase noise 5 MHz Oven Controlled Crystal Oscillator (OCXO). The key component of the frequency multiplication is a non-linear transmission-line (NLTL) as a frequency comb generator. Based on the principle of the NLTL, we carefully optimized the input power, the input and output impedances of the NLTL to suppress its excess phase noise. The measured results show that the absolute phase noises of 9.192 GHz signal are -64 dBc/Hz, -83 dBc/Hz, -92 dBc/Hz and -117 dBc/Hz at 1 Hz, 10 Hz, 100 Hz and 1 kHz offset frequencies, respectively. The residual phase noise of the synthesizer is − 82 dBc/Hz at 1 Hz offset frequency. The frequency stability limit due to the absolute phase noise via Dick effect is theoretically estimated to be 7.0 × 10−14τ−1/2.
A one-dimensional model for compressible fluid flows through deformable microchannels
Authors: Mehboudi Aryan , Yeom Junghoon
Published: September 2018

Fluid-structure interactions in low-Reynolds-number flows have received an increasing interest due to emerging bio-applications of deformable microfluidics. We utilize the lubrication theory and wide-beam framework to develop a one-dimensional coupled fluid-solid-mechanics model for the prediction of the characteristic behavior of compressible fluid flows through deformable microchannels. An explicit relationship is extracted for the mass flow rate as a function of pressure difference across a microchannel, undeformed channel dimensions, and properties of channel’s ceiling such as thickness, modulus of elasticity, and Poisson’s ratio. The resulting fifth-order algebraic equation is also solved numerically to obtain the pressure distribution within the microchannel. As a special case for compressible fluid flows, the characteristics of ideal gas flows are extracted from the general model. Rigid and deformable microchannels are fabricated, and the mass flow rates of air through the channels are measured under various pressure differences across the channels. The proposed model predicts the mass flow rate with an acceptable accuracy. Our experimental and theoretical results highlight the importance of fluid compressibility and microchannel deformability, demonstrating that neglecting either of them under sufficiently large pressure differences can lead to erroneous results. To the best of the authors’ knowledge, this is the first theoretical model simultaneously addressing both fluid compressibility and microchannel deformability for an equilibrium pressure-driven compressible fluid flow in microscale.
Invited Article: Saturation scattering competition for non-fluorescence single-wavelength super-resolution imaging
Authors: Ouyang Xueying , Qin Fei , Ji Ziheng , Zhang Tianyue , Xu Jian , Feng Ziwei , Yang Shenyu , Cao Yaoyu , Shi Kebin , Jiang Lingxiang , Li Xiangping
Published: September 2018

Stimulated emission depletion nanoscopy and its derivatives based on saturation induced competition effects have become an indispensable tool for studying cellular events and their dynamics in living conditions. The successful implementation of these techniques heavily relies on the competition between excitation induced spontaneous emission and stimulated emission from fluorescent dyes. The use of two laser beams at different wavelengths perplexes the optical system and the high intensity saturation beam inevitably introduces detrimental photobleaching effects. Harnessing the emerging saturation scattering of plasmonic nanoparticles, here, we demonstrate a novel fluorescence-free single-wavelength super-resolution imaging technique using gold nanoparticles. A lateral resolution of 101.2 nm (<λ/5) is achieved through introducing saturation scattering competition (SSC) of 60 nm gold nanospheres between dual beams at the same wavelength. In addition, the SSC drastically reduces the saturation intensity by three orders of magnitude than the conventional stimulated emission depletion process at comparable resolutions. As a proof of concept, we realized robust single-wavelength super-resolved imaging in dMG-63 cells with a simplified system. The current technique provides a new modality of biosample-friendly technology for optical super-resolution imaging.
Dual energy-band excitation from a low power Rh anode X-ray tube for the simultaneous determination of low Z and high Z elements (Na-U) using total-reflection X-ray fluorescence analysis (TXRF)
Authors: Prost J. , Wobrauschek P. , Streli C.
Published: September 2018

This article presents results from an experimental setup for a dual energy-band vacuum spectrometer for total-reflection X-ray fluorescence analysis allowing simultaneous efficient excitation of low, medium, and high Z elements. The spectrometer is equipped with an air-cooled 35 W low power Rh X-ray tube and a 17 mm2 silicon drift detector with a thin 8 µm beryllium window. A Pd/B4C multilayer monochromator is used at the same time as a Bragg reflector for Rh-Kα radiation and as a high-energy cut-off reflector above 5 keV, where the characteristic Rh-L radiation is totally reflected and present in the spectrum of the exciting radiation. This leaves one broad low energy band below 5 keV and one high energy band around the energy of Rh-Kα. As Rh-L radiation would be absorbed on its path through air, a new beam entrance system was designed in order to guide the Rh-L photons into the vacuum chamber for efficient excitation of low Z elements. With this setup, elements down to sodium (Z = 11, E = 1.04 keV) could be detected. First results are presented, and spectra obtained in air as well as in vacuum are compared and discussed. Detection limits in the range of 1000 µg/kg for Na and around 140 µg/kg for Mg were achieved using the NIST SRM 1640 (trace elements in water).
Hard X-ray induced fast secondary electron cascading processes in solids
Authors: Mecseki K. , Höppner H. , Büscher M. , Tkachenko V. , Medvedev N. , Bekx J. J. , Lipp V. , Piekarz P. , Windeler M. , Tisch J. W. G. , Walke D. J. , Nakatsutsumi M. , Prandolini M. J. , Glownia J. M. , Sato T. , Sikorski M. , Chollet M. , Teubner U. , Robinson J. , Toleikis S. , Ziaja B. , Tavella F.
Published: September 2018

Recent studies confirmed that the materials used in the extreme UV and soft X-ray regime for precise characterization of intense free-electron laser pulses (e.g., Si3N4) do not work efficiently in the hard X-ray regime, which is due to the fact that the impact of a hard X-ray photon is followed by a series of electron cascading processes. Following theoretical indication, we show that this limitation can be circumvented and the cascading time can be significantly reduced if the X-ray photon energy is double the ionization energy. We investigate an alternative material for pulse diagnostics, SnO2, using the Linac Coherent Light Source at photon energies of 5 keV and 9 keV. We prove the validity of the concept and show that it has a large potential for practical applications. By applying the proposed criteria, the temporal accuracy of the non-invasive pulse diagnostic tools can be improved in current and emerging hard X-ray facilities.
Interaction dynamics of longitudinal corrugations in Taylor-Couette flows
Authors: Ng J. H. , Jaiman R. K. , Lim T. T.
Published: September 2018

In this paper, numerical simulations are performed on the interaction of vortices with a longitudinal corrugated wall in a Taylor-Couette (TC) setting with the inner smooth surface cylinder rotating and the outer corrugated surface cylinder stationary. The motivation of the study is to shed light on how such an interaction affects the drag/torque with respect to two geometric parameters of the corrugations, namely, the wavelength λc* and amplitude A*, where * indicates a normalization by the gap width d. Results show that in the circular Couette flow regime, the secondary vortices induced by the corrugations cause the torque to increase. When λc*<1, there is a linear relationship between torque and λc*, and when λc*>1, there is a steeper increase of torque due to the interaction of the growing secondary vortices and the opposite wall. In the Taylor-vortex flow regime, the interaction between the Taylor vortices and the corrugations produces three distinct behaviors characterized by λc*. As the wavelength increases, our results show that the stronger modulation effects can override the inherent TC flow dynamics, which in turn leads to a wide range of flow structures that can have a significant impact on the resulting drag/torque characteristics. Generally, a torque reduction is achieved when λc*≤1, while forcing the Taylor vortices to stay on the crests of the corrugations can lead to significant improvement in torque reduction. Finally, the geometrical shape of the corrugations mainly alters the wall shear stress distribution on the corrugated wall, with a negligible effect on the flow dynamics when compared to λc*.
Large negative anisotropic magnetoresistance in Co2MnGa Heusler alloy epitaxial thin films
Authors: Sato T. , Kokado S. , Kosaka S. , Ishikawa T. , Ogawa T. , Tsunoda M.
Published: September 2018

Anisotropic magnetoresistance (AMR) effects in Cox(MnyGa1-y)100-x Heusler alloy thin films epitaxially grown on a MgO single-crystal substrate have been investigated by changing their composition in the ranges of x = 44.4–59.2 at. % and y = 0.44–0.55. Negative AMR ratios were observed at measurement temperatures from 5 to 300 K for all the films, indicating that Co2MnGa films have possible half-metallicity. The AMR ratio changed sensitively depending on the composition of the films. In the case of the film with y = 0.44, the AMR ratio peaked at around x = 50 at. %. In addition, the amplitude of the AMR ratio increased with decreasing y when x was approximately 50 at. %. As a notable result, large negative AMR ratios of −2.32% at 5 K and −0.82% at 300 K, whose amplitude is more than four times that of Co2MnSi films, were obtained for the Co−Mn−Ga films. These results suggest that the Co2MnGa films have a high spin polarization due to half-metallicity.
Investigation on the effect of pressure rate on formability of aluminum alloy during warm/hot sheet hydroforming
Authors: Cai Gaoshen , Wu Chuanyu , Gao Zepu , Lang Lihui , Alexandrov Sergei
Published: September 2018

Warm/hot sheet bulging tests of 2A16-O aluminum alloy were conducted using elliptical bulging dies under various temperatures and pressure rates, in an effort to investigate the macroscopic and microscopic influence of the pressure rate on the formability and microstructural evolution of hydrobulging parts during warm/hot sheet hydroforming. The results revealed that the forming limit of the aluminum alloy was clearly influenced by the pressure rate as the temperature rose, wherein a lower pressure rate resulted in a higher forming limit. Metallographic observations and Energy Dispersive Spectrometer (EDS) analysis revealed no obvious influence of the pressure rate on the microstructure of hydrobulging parts after warm/hot sheet hydroforming. This study demonstrates that warm/hot sheet hydroforming of aluminum alloy may lead to an improved forming limit and inhibit microstructural degradation during processing.
Communication: A hybrid Bethe–Salpeter/time-dependent density-functional-theory approach for excitation energies
Authors: Holzer Christof , Klopper Wim
Published: September 2018

A hybrid Bethe–Salpeter/time-dependent density-functional-theory method is described that aims at improving the performance of the GW/Bethe–Salpeter-equation (GW/BSE) method in general and for excited triplet states in particular. The static screened exchange W used in the BSE is combined with the correlation kernel of the underlying density functional in a manner that retains a proven feature of the BSE, that is, the correct description of charge–transfer excitations. The performance of the new method, labeled cBSE, is assessed using G0W0 or evGW quasiparticle energies, and an improved performance is observed. The cBSE approach shows nearly equal performance for excited singlet and triplet states, rivaling coupled-cluster theory (in the CC2 approximation) in accuracy at a computational cost that is at least one order of magnitude smaller.
Contributions of the glycocalyx, endothelium, and extravascular compartment to the blood–brain barrier
Authors: Kutuzov Nikolay , Flyvbjerg Henrik , Lauritzen Martin
Published: September 2018

Significance

The vascular endothelium constitutes the main barrier that restricts the transport of molecules from blood to brain. However, the barrier properties of structures adjacent to the vascular endothelium are understudied. Based on two-photon microscopy imaging of single cortical capillaries, we found that the blood–brain barrier (BBB) consisted of at least three elements: the endothelial glycocalyx, which forms a barrier on the blood side to large but not small molecules; the endothelium; and the basement membrane and astrocyte endfeet—the final line of defense on the brain side. All three elements restricted permeation of large molecules and should be taken into account when studying drug delivery and disease states.
Relation between single-molecule properties and phase behavior of intrinsically disordered proteins
Authors: Dignon Gregory L. , Zheng Wenwei , Best Robert B. , Kim Young C. , Mittal Jeetain
Published: September 2018

Significance

Some proteins can undergo phase separation in vivo to form membraneless organelles with distinct physiological functions. In many cases, the driving force is believed to be the intrinsically disordered domains that lack regular structural features and can phase separate in vitro. Relating protein sequences to phase-separation propensity is the goal of this work. Toward this goal, we highlight the connection between the temperature where a single chain collapses, the temperature where interactions within a dilute solution favor self-association, and the critical temperature of phase separation. Our results show that these characteristic temperatures are highly correlated, suggesting that experiments performed in dilute conditions may be used to predict phase separation.
Seed preparation.
Authors: Kelanaputra E. S. , Nelson S. P. C. , Setiawati U. , Sitepu B. , Nur F. , Forster B. P. , Purba A. R.
Published: September 2018

In order to collect fresh seeds from harvested bunches, the fresh bunch is chopped using an axe (a trained worker must be assigned to this job) to separate the spikelets from the stalk. Fruits attached to spikelets are fermented for 3-4 days in an area separate from the detached fruits. Detached fruits are peeled by hand by a skilled person using a sharp knife. Detached fruits are placed in a de-pulping machine to remove the mesocarp from the seed (nut). Seeds that still have fibre are cleaned by scraping with a sharp knife; this reduces fungal contamination. The clean fresh seeds are then treated with a disinfectant and fungicide solution for about 3 min and placed into perforated trays to dry in the open air under a fan for about 24 h. The dried seeds are sorted to remove off-types (white, small and broken) and transferred to slow drying conditions at 19-23°C for about 24 h.
Seed viability testing.
Authors: Kelanaputra E. S. , Nelson S. P. C. , Setiawati U. , Sitepu B. , Nur F. , Forster B. P. , Purba A. R.
Published: September 2018

Seed viability testing in seed processing is carried out to forecast germination levels. The test is destructive and involves removing the embryo from the kernel for visual inspection.
Seed moisture testing.
Authors: Kelanaputra E. S. , Nelson S. P. C. , Setiawati U. , Sitepu B. , Nur F. , Forster B. P. , Purba A. R.
Published: September 2018

Seed moisture content is critically important for efficient seed processing. In order to achieve the highest seed germination, the moisture must be controlled: if it is too low, the seed will die; and if too high, it will stimulate fungal growth and result in seed loss during processing.
Seed production for breeding.
Authors: Kelanaputra E. S. , Nelson S. P. C. , Setiawati U. , Sitepu B. , Nur F. , Forster B. P. , Purba A. R.
Published: September 2018

Seed production processes for breeding follow the same basic processes as described for (Dura) commercial seed. Breeding seed may be either Dura (thick shelled) or Tenera (thin shelled). As in commercial production, oil palm breeding seeds require heat treatment before germination will start. Seed processing procedures described in Chapters 6-9 of this manual should be implemented, but the target is dependent on the numbers of germinated seeds required for breeding purposes, e.g. trialling. Also, Tenera seeds, which are thin shelled, are treated slightly differently to thick-shelled Dura seeds during the heating step to break dormancy. Normally, Tenera seeds have a lower germination rate compared to Duras, due to them being more susceptible to fungal attack.
Health and safety considerations.
Authors: Setiawati U. , Sitepu B. , Nur F. , Forster B. P. , Dery S.
Published: September 2018

All field and laboratory operations should have standard health and safety protocols. These may vary according to local requirements and standards. Some equipment will also come with instructions on proper use, which may involve training, including health and safety issues. Failure to abide by these can result in accidents and personal injury (serious and minor); neglect of health and safety issues may incur penalties such as fines or cessation in field and laboratory activities. Guidelines in health and safety issues relating to crossing in oil palm are given below.