bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Morphology and Doping of Titania Nano-porous Materials for Efficient Oxidation of Air Contaminants
Authors: Ghezzo F
Published: April 2021

Air pollution is a global concern. Public and governments sensitivity to matters related to air pollution has been constantly increasing since the 1970’s. The urgency to lower greenhouses emissions in order to protect the environment and its wildlife while mitigating the impact of pollution on people’s health reflects into the growing private and government investment on green technologies for renewable energy and sustainable products. Along with CO2, there are other pollutants that affect the quality of the air we breathe. Among them, nitrogen oxides. To neutralize their effects, the research community has been synthesizing photocatalysts capable to oxidize them. The work focuses on the synthesis of doped titanium dioxide by sol gel method and on the influence of the calcination temperature on the final material photo-oxidation ability.
New Governance Ways Aimed at Protecting Nature for Future Generations: The Cases of Bangladesh, India and New Zealand: Granting Legal Personhood to Rivers
Authors: Willems M , Lambooy T , Begum S
Published: April 2021

Recently, three important rivers in Asia and Oceania were acknowledged as legal persons. Questions emerge, such as: Which motivation drives the people who urged the respective courts and governments to grant these rivers legal personhood, in other words, to create Rights of Nature? Do these events lead to transformative social innovation and change our perspectives of how we see nature? As methodology we employ doctrinal research, examining original legal documents and contemporary news sources concerning the three grassroots initiatives on the rivers. The analysis reveals that there are different reasons for proposing this innovative legal approach of creating Rights of Nature. They include: providing people access to clean rivers for drinking water, sanitation, transportation and agricultural purposes; preventing the river from disappearing; addressing the issue of pollution and toxicity of river water; acknowledging the divine status of the river; and honouring indigenous beliefs concerning the river. The research findings demonstrate transformative social innovation: in all three cases, grassroots initiatives led to a system change. Moreover, dissemination of information concerning individual cases inspires other societal groups to reconsider the situation of their own ecosystems and to develop innovative governance possibilities, thereby honouring an alternative worldview in which human beings see themselves as part of nature rather than owning it just for utilitarian purposes.
A Novel Method for State of Charge Estimation of Lithiumion Batteries using Embedded Cubature Kalman Filter
Authors: Xu J L , Xu W , Huang F G , Xia W , Liu B L
Published: April 2021

The accurate estimation of state of charge (SOC) of Lithium-ion battery is one of the most crucial issues for battery management system (BMS). This paper proposes a novel method for SOC estimation using the embedded cubature Kalman filter (ECKF). ECKF computes the cubature points with a weight depends on an optional parameter, which differs from the standard cubature Kalman filter (CKF). An online model identification method for a second-order RC networks equivalent circuit model using the forgetting factor recursive least squares (FRLS) algorithm has been presented. The Dynamic cycles are used to assess the superiority in improving the accuracy and stability of proposed method compared with the widely used algorithms. Experimental results show that, with 20% initial SOC error, the maximum estimation error is within 1%, which indicates that the proposed ECKF method has higher estimation accuracy and robustness for SOC estimation.
Application of Solar Radiation Analysis Technology in the Optimization of Campus Planting Design
Authors: Hsu Che-Yu , Ou Sheng-Jung
Published: April 2021

In recent years, the slogans and concepts of sustainable campus, eco-campus, and environmental protection campus have been continually put forward, but there is little ink about the maintenance and management of the most important plants on campus. However, landscape designers often neglect the requirements of plants for the growth conditions of sunlight, or the impact of surrounding buildings on the living environment of plants, resulting in an irreversible situation. To this end, this research hopes to use environmental analysis aided design software to simulate the solar radiation environment and provide references for campus planting design and suggestions for plant selection. The results show that sciophytes are suitable for planting in areas where solar radiation energy is less than 2.90 MJ/m2d; Heliophytes are suitable for planting in areas where solar radiation energy is greater than 5.40 MJ/m2d, and the area in between is suitable for planting mesophytes.
Numerical Study of NOx Generation in a Trapped Vortex Combustor Fuelled by Kerosene Blended with Ethanol
Authors: Yan Peiliang , Fan Weijun , Xu Hanqing , Zhang Rongchun
Published: April 2021

The study of alternative fuels is of great importance, and the study of ethanol blended with kerosene is necessary. The trapped vortex combustor is a new type of combustor and NOx emissions are important in the study of trapped vortex combustors. In this article, the NOx generation rate of trapped vortex combustor was studied using kerosene blended with ethanol in different mass fractions as fuel. The results show that the thermal NOx is the main source of NOx in the combustor, which is mainly generated at the back of the combustor, and the thermal NOx generation rate decreases with the increase of ethanol mass fraction. The prompt NOx generation rate decreases with the increase of ethanol mass fraction. NOx is also easily produced near the sidewall of the combustor.
A Study on Public Environmental Risk Perception and Environmental Behavior of Urban Space - A Case Study of the East District of Taichung City
Authors: Hsu Kuo-Wei , Chao Jen-Chih , Hsu Ching-Yi
Published: April 2021

The contemporary living environment in Taiwan is affected by traffic, industry, and seasonal air pollution. Wearing masks outside the home environment has become a daily habit for a number of people. The Taiwanese government encourages people to wear masks when using the mass transit system and in public spaces, to impose social distancing, and prohibits large-scale activities to reduce exposure to environmental risks after the outbreak of COVID-19. By April 13th 2020, no new local cases of COVID-19 had been reported for more than 30 consecutive days. This study examines open and semi-open spaces using non-participatory observation method to understand public mask-wearing of environmental behavior. The results of the study show that the proportion of people wearing masks in open spaces is only 16.8%, and that the proportion of those wearing masks in semi-open spaces is 61.1%. This shows that the public continues to maintain a cautious attitude towards COVID-19 and that their perception of the environmental risks and environmental behavior differs across different spatial environments.
The Utilization of Sedimentation Pond Acid Mine Drainage Sludge as Coagulant to Reduce COD and TSS Concentration in Domestic Wastewater
Authors: Daradjat Nurul Shafira , Moersidik Setyo Sarwanto
Published: April 2021

Acid mine drainage (AMD) treatment leaves residue in the form of sludge that contains large amounts of metal, silica, ferric, and alum. This research aims to determine the capabilities that AMD sludge-synthesized coagulant has in reducing COD and TSS concentration in domestic wastewater. The domestic wastewater sample used in this research is an artificial domestic wastewater with a COD concentration of 285 mg/l and a TSS concentration of 245.31 mg/l. After going through Acidification process, AMD sludge coagulant contains Si (43.66%), Fe (30.02%), dan Al (12.35%). A jar test is then performed in order to determine the optimal coagulant dosage. In this process, a coagulant dosage of 40 mg/; 60 mg/l; 80 mg/l; 100 mg/l; 140 mg/l; 180 mg/l; and 200 mg/l was used with 100 mg/l being the optimal coagulant dosage. The AMD sludge containing the optimal coagulant dosage of 100 mg/l is found to be able to reduce COD concentration by 34.74% and TSS concentration by 95.63% from the tested domestic wastewater sample. This research can illustrate the vast potential that the AMD sludge has as a coagulant.
Health Assessment in View of Environmental Quality in Krasnoyarsk Territory (Siberia, Russia)
Authors: Koptseva N P
Published: April 2021

This article presents the results of comprehensive field studies carried out in the Krasnoyarsk Territory. The objective of the research is to assess the impact of the environmental situation in the Krasnoyarsk Territory on its population’s health for expert analytical guidance in environmental management in the given region and to gain an objective picture of this assessment. Questionnaires were handed out that provided answers to 41 questions about environmental problems, including questions on assessing the impact of the environmental situation on the health of the Krasnoyarsk Territory population. The following data was obtained from 967 of these questionnaires: assessment of the impact of the environmental situation on the health of the Krasnoyarsk Territory population. The proportion of people who believe that the environmental situation has impacted their health adversely is 50.5%. The Krasnoyarsk Territory population is also convinced that air pollution is the most pressing environmental problem. The majority of respondents do not consider climate change or poor waste management to be the cause of the worsening environmental situation in the region that is leading to the deterioration of their health and that of their families.
Heterotrophic and Mixotrophic Cultivation of Chlorella vulgaris using Chicken Waste Compost as Nutrients Source for Lipid Production
Authors: Tan Hong Li , Lam Man Kee , Cheng Yoke Wang , Lim Jun Wei , Tan Inn Shi , Henry Foo Chee Yew , Show Pau Loke
Published: April 2021

Microalgae have received global attention for the past decades as it shows promising results to be an alternative and sustainable energy resource due to their high growth rate and lipid production. In commercial microalgae cultivation, autotrophic method is always used to grow the microalgae. However, this method usually produces high biomass yield but low lipid content. One of the approaches to enhance the microalgae lipid yield is through heterotrophic and mixotrophic method, in which dark environment and organic carbon are introduced as a stress factor to induce the lipid productivity. In the present study, cultivations of microalgae were done using chicken compost and glucose under autotrophic, heterotrophic and mixotrophic conditions. The highest absorbance attained for both heterotrophic and mixotrophic cultivation conditions were 1.650 and 2.184 respectively when 1.0 g/L of glucose was used. Absorbance and biomass are correlated, therefore the absorbance in this study signifies the amount of biomass produced. Moreover, the highest lipid yield was successfully attained at 45 wt% under mixotrophic condition. Overall, the lipid yield of microalgae cultivated under mixotrophic was higher than the heterotrophic condition when compost derived from chicken waste was used as nutrients source.
A Review in Tetracycline Removal from Water Environment by Carbon Nanotubes Adsorption
Authors: Yang Dailin
Published: April 2021

Owing to the unique properties, carbon nanotubes (CNTs) have been widely reported as a desirable adsorbent for environmental pollutants removal. In this paper, the synthetic strategies of different kinds of CNTs and CNTs based composites, as well as their application in tetracycline antibiotics (TCs) removal were discussed. The adsorption process, performance, influence factors involved in the adsorption of tetracycline (TC) are highlighted in this review. In addition, the adsorption mechanism and limitations in adsorption TCs with CNTs are discussed.
Evaluation of the sustainability of the urban development sector in Iraq
Authors: Ameen Raed Fawzi Mohammed
Published: April 2021

Aim: Sustainability is now considered an important consideration of the urban development sector in terms of reducing undesirable impacts on human life and environment. This has led to the development of best-practice patterns and integrated elements of urban planning and design and the implementation of sustainable technology scenarios. Furthermore, urban development projects to promote unique solutions for various urban fields, as well as access to the potential inherent in urban development projects, whether existing, planned, or under construction, have been identified as extremely important. Identifying local urban challenges to existing development projects by investigating stakeholder perceptions can help determine the actual situation and offer an accurate view of the size of the challenges faced by such projects. Furthermore, measuring such projects’ quality, performance, and applicability in different urban environments, particularly in developing economies, such as Iraq is necessary.

Methods: A national survey was conducted to identify and investigate crucial challenges faced by the urban development sector in Iraq. Several important statistical tests were then applied to investigate the relationships between the identified items and the demographic characteristics of respondents, as well as to evaluate the sustainability of study indicators in terms of availability, public acceptance, and quality from stakeholders’ perspective in Iraqi cities. Results: The survey achieved a response rate of 59.4% (n = 1,496) across all Iraqi regions. An 18-item scale related to the main topic was thus presented, with stakeholder’s perceptions on each item evaluated on a 6-point Likert scale. Public awareness of the importance of sustainability was reflected in the fact that about 42%of the respondents were highly concerned with urban development, and well informed about sustainability issues. This offers an optimistic take on people’s interest in sustainable urban projects in Iraq. About 71% of the participant were prepared to pay extra fees to live in a sustainable city in the future. However, the “Use of renewable energy” (mean = 1.77) was ranked lowest, based on it being generally “not available” for use.

Conclusion: the urban development sector in Iraq faces numerous challenges, both in terms of service quality and availability. This reflects an urgent need for the immediate development of sustainable practice in urban development projects.
Finite element analysis of a zoned earth dam under earthquake excitation
Authors: Jawad Areej A , Hassan Waqed H , Fattah Mohammed Y
Published: April 2021

This paper presents a finite element analysis of a zoned earth dam under the effects of earthquake conditions. GeoStudio software, and in particular the sub-programs SEEP/W and QUAKE/W were used, and the earthquake used in the analysis was an Iraqi earthquake that occurred in Ali Al-Garbi, within the Missan governorate. The Haditha dam section data was used for the hypothetical dam construction. The total length of length of this dam is 9,064 metres, which includes 8,875 metres of earth fill, and the maximum height of the dam is 57 m. The shell is constructed from a mix of sand and gravel, with an average particle diameter ranging from 0.24 to 16.7 mm. Three different properties were used to represent the core material, and each of these properties was analysed under three different heads of water on the upstream side. The results showed that high water levels at the upstream side of the dam heavily influenced the analysis results. The water flux, water conductivity, and peak displacement all increased with the increase in the water level upstream of the dam. For a water level equal to 152 m, the maximum values of water flux, water conductivity, and maximum displacement were 3.951 × 10-3 m2/sec, 6.654 × 10-3, and 2.03 m, respectively, while where the water level was 143 m, these values were equal to 2.023 × 10-3 m2/sec, 3.995 × 10-3, and 1.85 m, respectively. Further analysis showed that the water flux, water conductivity, and peak displacement increased with increases in the void ratio and degree of saturation of the clay core material, moving from 2.023 × 10-3 to 3.951 × 10-3 m2/sec for water flux, from 3.995 × 10-3 to 6.654 × 10-3 for water conductivity, and from 1.85 to 2.03 m for peak displacement.
Investigation on Cutting Feasibility on Ni-CBN on HSS Substrates for Aerospace Material
Authors: Azinee S. N. , Norsilawati N. , Bahiyah Baba N. , Fathil C. I. M. , Ibrahim Mohd. H. , Izzat R. A. N.
Published: April 2021

The study involves coating the high-speed steel (HSS) tool with cubic Boron via electroless nickel co-deposition. The surface coating of Ni-CBN was deposited via electroless nickel where the process of involved chemical reactions as the ceramic CBN powders was embedded within the layer. By introducing the electroless nickel process, the coating cost and procedure could be simplified. The electroless deposition has been extensively practised in industry, and the most prevalent coating offers excellent corrosion, wear and abrasion resistance, ductility, lubricity, electrical properties, and hardness. Thus, the introduction of the new electroless nickel (Ni-CBN) tools can be a contribution to the industry. This paper discussed on comparing the performance of Nickel-cubic boron nitride (Ni-CBN) HSS tool substrates and with uncoated HSS tool for its surface tolerance in milling of Aluminium Alloy 7075. The process variables selected during experimentation based on Taguchi L9 are cutting speed, feed rate, and depth of cut with three different levels for each parameter. Result shows, the lowest flank wear for coated measured is 51.34 μm while the highest is 380.26 μm. The highest surface roughness for uncoated is 1.154 μm and lowest 0.42μm. Meanwhile, for coated substrates, the highest Ra is 0.787μm and lowest 0.251μm. At the end of the analysis, the Ni-CBN HSS cutting tools are generally able to slightly reduce the tool wear with the longest tool lifetime 195 minutes compared uncoated 143 minutes. Therefore, it is concluded that the Ni-CBN HSS tool end mill are generally able to reduce the tool wear.
Smart Helmet
Authors: Sobhana S , Sowmeeya S R , Srinathji M , Tamilselvan S
Published: April 2021

According to the investigation in India, nearly 25% of the road accidents are caused by two wheelers. The foremost causes for the fatalities are due to drunken driving, rash driving, and drowsiness due to long drive. The aim is to build an interesting smart helmet that protects us from accidents and indicates the accident prone area. Here we are using various sensors to build the smart helmet. To detect alcohol consumption of the rider we use Alcohol sensors. In order to check a rider’s helmet, an infrared sensor can be used. Vibration detector is also added to the helmet to indicate the harsh hitting of the helmet during an accident. When the two wheelers slide down due to road rashes, the GPS is used to identify the location of the accident spot and quickly sends messages (location) to police stations and hospitals nearby through GSM.
Design and Implementation of IoT Based Soil Moisture Data Logger for Irrigation and Research Applications
Authors: Satheesan Abin , Deb Sanjoy , Shri Tharanyaa J.P.
Published: April 2021

A fundamental way to schedule irrigation is possible through the continuous monitoring and management of soil moisture. Soil moisture is directly related to soil water content and this water content will affect the quantity of nutrients available to plants and soil aeration status. Proper irrigation can be done with the help of the accurate measurement of soil moisture. This proposed system is capable to collect the soil moisture content using watermark 200SS sensor and will be recorded in the permanent storage medium and will be accessible through wireless media. The soil moisture value is calculated in Centibar (cb) or Pascal ( SI unit ) based on the resistance value of soil moisture sensor and temperature sensor.This cost-effective system will be useful for irrigation, automatic plant watering, and get the details of the soil moisture. The system has been tested in different environmental conditions and verified the values. The system is completely powered by solar energy and consuming very less amount of processing power to run.
An evaluation of highway crash-prone areas: A case study on Pan Borneo Highway in the state of Sarawak
Authors: Tan S L , Kabit M R , Johnson O A
Published: April 2021

Road traffic crashes is one of the major causes of death that needs to be addressed globally. Many studies have been conducted to identify the contributing factors to traffic crashes and to determine the required preventive measures. This study evaluates the causes of 164 traffic crashes along a 10 kilometres section of Pan Borneo Highway Sarawak. The study investigated the main causes of traffic crashes within this section of road through multiple sources: based on expert on site evaluation, analysis of site incident report and police accident record. The finding reveals that most of the accidents (93%) occurs during the daytime, weather contributes a combined 69% and private car owners (80%) cause most of the traffic crashes. The study also indicates that the road condition is a significant factor to the occurrence of traffic crashes in that area contributing 64% of the total crashes.
Structural and thermoluminescence property of Y6Ba4(SiO4)6F2:Ce, Tb
Authors: Sahu Pailendra Kumar , Agrawal Sadhana
Published: April 2021

Present paper reports the synthesis, structural, morphological and thermoluminescence behavior of Y6Ba4(SiO4)6:Ce,Tb apatite phosphors prepared by solid state reaction method. X-ray diffraction pattern confirms the formation of Y6Ba4(SiO4)6:Ce,Tb into apatite structure. Morphological study was done by scanning electron microscope (SEM) and it reveals that the prepared phosphors have rod-like structure with different orientation. Energy dispersive spectroscope (EDX) confirms the presence of initial reactant. Thermoluminescence glow curve of the prepared phosphors were studied and its frequency factors, activation energy, order of kinetics etc are calculated and reported in the present paper.
Optical characterization of CTAB assisted Ni doped ZnS nanoparticles
Authors: Ojha K S , Saini S M
Published: April 2021

Ni doped zinc sulphide nanoparticles at different concentration of CTAB have been prepared via solvothermal route. The structural characterization of the ZnS:Ni nanoparticles has been made using XRD technique and it reveals cubic zinc blende structure of ZnS. The crystallite size calculated from the XRD pattern is in close agreement to that estimated from the TEM image. The UV-Vis study of ZnS:Ni nanoparticles indicates the red shift in the absorption peak as compared to bulk ZnS. The emission spectra ZnS:Ni sample at 5 mmol CTAB concentration has been fitted into three Gaussian peaks.
In-vitro molecular interaction of boron doped carbon dots with human serum albumin
Authors: Sahu Vinayak , Khan Fahmida , Dewangan Pradeep Kumar , Kashyap Komal , Agrawal Sonalika , Jain Vikas Kumar
Published: April 2021

Carbon dots have drawn prodigious attention in biomedical and biological fields by virtue of its unique optical properties, but their effect on structure and behaviour of essential proteins have rarely been explored. In this study boron doped carbon dots (BCDs) which was synthesized by microwave treatment of citric acid, boric acid and urea, with maximum emission wavelength of 444 nm when excited upon long wavelength ultra-violet light. Synthesized BCDs were characterized by UV-Visible, FTIR, HRTEM and Fluorescence spectroscopy. Interaction between BCDs and human serum albumin (HSA) is carried out in physiological conditions. Stoichiometry of BCDs-HSA was found to be 1:1 and various thermodynamic parameters have also been calculated. The negative value of ΔG suggested that interaction between HSA and BCDs was spontaneous in nature.
Synthesization and optical characterization of photovoltaic materials for perovskite solar cell application
Authors: Dongre Y K , Roy P , Khare A , Tiwari S
Published: April 2021

The performance of Perovskite solar cells (PSCs) has rapidly increased over the last decade. The power conversion efficiency (PCE) of 25.2% has been reported. Drastic and rapid change in PCE of PSCs has attracted a lot of attention toward this alternative photovoltaic technology that can be manufactured using simple and low cost processing techniques, over the traditional silicon solar technology. Here in this work, we have synthesized Molybdenum trioxide (MoO3) and Titanium dioxide (TiO2) for charge transport materials application in PSC application. The analysis of materials has been carried out by photoluminescence and absorbance spectra. The results signify that MoO3 has absorbed at the visible region around (600-800) nm and the absorbance of TiO2 tuned at 400 nm. Due to high absorption range (600-800) at visible region MoO3 is suitable for Hole Transport Material (HTM). The widely used Electron Transport Material (ETM) TiO2 is also synthesized and characterized.
Impact of hole transport layer on the performance of all-inorganic tin (Sn) based perovskite solar cells
Authors: Roy P , Dongre Y K , Tiwari S , Chaturvedi D , Khare A
Published: April 2021

The power conversion efficiency (PCE) of perovskite solar cells (PSCs) has shown vast increment from 3.81% to 25.5% within a decade. Despite the fast progress and many advantages, these cells are facing an issue of toxicity and poor device stability. In this work, we deal with the issue of toxicity by using Tin (Sn) instead of Lead (Pb). The PSCs are simulated using Solar Simulator Capacitor (SCAPS-1D version 3.3.07) software. We used all-inorganic, lead free material, Cesium Tin–Germanium Tri-iodide (CsSn0.5Ge0.5I3) as an absorber material. We further investigate the influence of hole transport layer (HTL) on the performance of Sn based PSCs. Simulation and analysis of following CsSn0.5Ge0.5I3 based PSC devices have been done: using (i) HTL free configuration (ii) inorganic HTL and (iii) organic HTL. The simulated cells are in planar n-i-p architecture. This work depicts the fact that Sn based PSCs have a potential to serve as high performance solar cells. The results signifies the impact of HTL on the performance of PSCs, in this study, we also suggest alternatives to the widely used HTM (Spiro-OMeTAD) that not only produce comparable photovoltaic performance but also are cost effective. We also analyse the influence of using various metal cathodes on the simulated cell. The result suggests that presence and type of HTM is having an impact on the contact selection criteria. The influence of HTL thickness variation on the performance of the PSCs are also studied.
Simulation and analysis of schottky junction perovskite solar cells (SJPSCs)
Authors: Sinha Numeshwar Kumar , Roy Priyanka , Ghosh Dhriti Sundar , Khare Ayush
Published: April 2021

The Schottky junction solar cells are the simplest and single-layer structure of solar cells, offering low-cost and easy fabrication. In this study, we have simulated and analyzed the Schottky junction perovskite solar cells, having the device structure of FTO/MAPbI3/Au. The simulation has done by Solar Cell Capacitance Simulator (SCAPS-1D). In this simulation, we have studied the effect of an absorber layer thickness, doping density, defect density, and the cell’s temperature on the performance of the cells. We have further studied the effect of different back electrodes, like Au, Cu, Ag, Al, and Graphene in the performance of cells. The effect of series and shunt resistance has also been studied at optimized parameters. This simulation suggests that the SJPSCs show the highest optimized power conversion efficiency of greater than 14%, at actual series and shunt resistance of the cell. Simulating this simplest structure will help to further improvement in the performance of SJPSC. However, the use of lead makes the solar cells non-eco-friendly, but the proper encapsulation and disposal management can solve this problem.
Observation of coronal mass ejections in association with sun spot number and solar flares
Authors: Gour Preetam Singh , Singh Nitin P , Soni Shiva , Saini Sapan Mohan
Published: April 2021

The sun’s atmosphere is frequently disrupted by coronal mass ejections (CMEs) coupled with different solar happening like sun spot number (SSN), geomagnetic storms (GMS), solar energetic particle and solar flare. CMEs play the important role in the root cause of weather in earth’s space environment among all solar events. CMEs are considered as the major natural hazardous happening at the surface of sun because this event can cause several other phenomena like solar flare and many more. In this work, we report a statistical observation for the relationship of CMEs having linear speed >500 km/s with SSN and solar flares that were registered during the period 1997-2015. Test results of the annual correlation between SSN and CMEs is 0.77 and can be represented by a linear regression equation. We concluded that SSN and solar flares are well correlated with CMEs in most of the yearly compiled data for this time span.
DFT study of adsorption and diffusion of Mg, K, Ca over monolayer antimonene
Authors: Upadhyay S , Srivastava P
Published: April 2021

Density Functional theory (DFT) based calculations are carried out to investigate adsorption and diffusion properties of Magnesium (Mg), Potassium (K) and Calcium (Ca) over single layer antimony (Sb) i.e. antimonene. Ca has highest value of absolute adsorption energy followed by K and Mg respectively. Charge transfer is greater in case of K adsorbed antimonene as compared to both of the other metals. This affects the electronic properties such as bandstructure and density of states. Antimonene is semiconducting in its pristine form. The adsorption of K leads to a shift to metallic nature, whereas Mg and Ca adsorption still maintain the semiconducting nature after reducing the bandgap. Diffusion of these metals shows that K can easily diffuse through the antimonene surface as compared to the Mg and Ca. The value of diffusion barrier for Mg, K and Ca is 0.30, 0.12 and 0.43 eV respectively. The effective adsorption and charge transfer along with low values of diffusion barrier suggests that phosphorene can be explored further as potential candidate for metal-ion batteries.
Study of adsorption of methylene blue in aqueous solution onto activated carbon prepared using low cost domestic oven based heating system
Authors: Sahoo Sinmay , Devi Maya , Kumar Das Susanta
Published: April 2021

In this work activated carbon was prepared from teak wood charcoal using very low-cost oven based heating system. Firstly, charcoals were grinded with a domestic grinder and then activated with 25% CaCl2 solution and then heated with 250C for different times. And then experiment was carried out through 2.5 × 10-5 methylene blue aqueous solution by taking activated Charcoal into it and kept one hour for adsorption. Adsorption capacity was estimated by taking the different amount of activated carbon. The result indicates that prepared activated carbon be effectively used for water purification application through adsorption of the dye.
131I radioactive self-expandable metallic stents for the therapy of malignant biliary obstruction
Authors: Liu Meirong , Hou Mengfei , Wu Qinghe , Zhang Chunfu
Published: April 2021

Biliary stent implantation has become a standard approach for patients with unresectable malignant biliary obstruction. Unfortunately, in-stent restenosis after stent implantation still occurs because of tumor overgrowth. The majority of studies show that radioactive stents harbor both the obstructed biliary tract-dilating and tumor-suppressing functions. In this study, we designed a kind of novel 131I-labeled radioactive self-expandable metallic stent (SEMS) that combines the mechanical dilation forces induced by stent expansion and 131I intraluminal brachytherapy, which was prepared by first coating the SEMS with poly (diallyl acrylate) (PDA) and then labeling with iodine-131. The designed stents would not only have a longer patency time but also is able to inhibit biliary compression caused by tumor growth. The PDA coating was robust and flexible. The 131I labeling rate was about 60%, and after a 16-day test of radiochemical stability of 131I, the radioactive stability was around 80%. In addition, the radiochemical stability of 131I could be improved by PDA recoating post-131I labeling. In conclusion, we designed and fabricated a kind of novel 131I-labeled radioactive self-expandable metal stents by labeling 131I on the PDA-coated stent. We provide a new idea of radioactive stents design, which would extend the patency time of the stent while reducing the rate of stent restenosis after implantation.
Study on performance improvement of oil well cement slurry by poly ether ether ketone
Authors: You Fuchang , Tian Jin , Shu Man
Published: April 2021

After the oil well cement solidifies, the internal original void causes the inherent strength of the cement stone to be insufficient, and the structural integrity of the cement stone is damaged after the external load, which is not conducive to the subsequent oil and gas exploitation. In order to make up for the inherent deficiency of cement paste strength, the effect of PEEK with high strength and high elastic modulus on the properties of oil well cement was studied. The conventional properties and mechanical properties of PEEK cement paste with different contents were evaluated. The microstructure of PEEK cement paste was observed by scanning electron microscope. The experimental results show that compared with the cement paste without peek, the rheological properties of cement paste with 1% ∼ 6% peek are worse, the thickening time is shorter, and the water loss is reduced. After curing for 28 days, the compressive strength of 5% peek cement paste decreased by 15%, the flexural strength and impact strength increased by 21% and 11% respectively, and the elastic modulus decreased by 50%. Peek is uniformly dispersed and filled in the cement paste. When the cement paste is subjected to external load, peek will deform, absorb part of the energy and hinder the crack propagation, which improves the ability of the cement paste to resist external load.
Experimental research on four-point-bending loading of composite fuselage frame
Authors: Xiang Li , Xingfu Li
Published: April 2021

A four-point-bending loading test device was designed for the pure bending loading of the composite fuselage curved frame. The reinforcing subplates, reinforcing frames, wedge-shaped blocks and other parts were installed in the load segment of test pieces to enhance the local stiffness, strength and torsional stiffness. Four-point-bending loading tests and nonlinear finite element calculation of C-frame and Z-frame pieces under the condition of positive bending was carried out. The calculated buckling mode was in good agreement with the test result, which provides a certain theoretical basis for the instability mode analysis of curved frames. The test and analysis results show that under the condition of positive bending and the middle section of C-frame has lateral instability and the end inner edge of the frame has the local buckling and damage. While the middle section of inner edge of the Z-frame has only local buckling and damage. The test results of two kinds of frame show that the stability and structural strength of Z-frame are better than that of C-frame.
Effects of reuse on the properties of tantalum powders and tantalum parts additively manufactured by electron beam powder bed fusion
Authors: Guo Yu , Chen Chao , Wang Qiangbing , Liu Min
Published: April 2021

The cost of additively manufactured tantalum parts can be effectively lowered by reusing or recycling tantalum powder. To evaluate the effects of reuse of the tantalum powder on the properties of tantalum parts and scaffolds, this study investigated the characteristics of tantalum powder during cycling, including oxygen content, particle morphology, apparent density, tap density, and flowability. Besides, the influence of reuse time on the mechanical properties of electron beam powder bed fusion (EB-PBF) fabricated tantalum parts and scaffolds was studied with tantalum powder reused more than 30 cycles. The results indicated that particle size distribution of the tantalum powder was nearly unchanged with the increase of cycle number, accordingly apparent density, tap density, and fluidity. While the powder became less spherical with increasing reuse times and some particles showed noticeable distortion and rough surface after being reused 25 times. Moreover, the oxygen content of the tantalum powder increased progressively with increasing reuse times, leading to the decrease of plasticity of the dense tantalum after 15 reuse cycles, and some potential micro-defects appeared in the tantalum samples fabricated from EB-PBF process. However, the tensile strength of dense tantalum parts was not sensitive to the number of uses within the research range.
Thermostructural and fluorescence properties of enterolobium cyclocarpum extract embedded in a silica xerogel matrix
Authors: Martínez J R , Ortega-Zarzosa G , Nieto-Villena A , Velázquez Pérez S E , Montiel-Palma S , Herrera-González A M , Galván-García E , Guerrero A Lobo
Published: April 2021

This work deals with the fluorescence behavior exhibited by extracts of parota wood (enterolobium cyclocarpum) when are embedded in a silica matrix, and the effect of the temperature on the emission and structural properties. The organics were incorporated into a silica matrix using the sol-gel method, and the resulting hybrid composite was subjected to different heat treatments to study its thermal stability and the effect on their structural and fluorescence properties. The structural properties were studied using x-ray diffraction (XRD), and the organics were analyzed by infrared spectroscopy (FT-IR) and fluorescence spectroscopy. Results show that the silica matrix avoids the thermal decomposition of the organics, and the structural changes of the silica impact on the fluorescence properties. In this sense, the maximum emission obtained at 400 °C was three times higher than the RT. This behavior was attributable to the strong interactions between the cellulosic compounds and the silica. Also, the cellulosic compounds promote the formation of open Si-O arrangements.
Precision integration of grating-based polarizers onto focal plane arrays of near-infrared photovoltaic detectors for enhanced contrast polarimetric imaging
Authors: Feng Bo , Chen Yifang , Sun Duo , Yang Zongyao , Yang Bo , Li Xue , Li Tao
Published: April 2021

Polarimetric imaging enhances the ability to distinguish objects from a bright background by detecting their particular polarization status, which offers another degree of freedom in infrared remote sensing. However, to scale up by monolithically integrating grating-based polarizers onto a focal plane array (FPA) of infrared detectors, fundamental technical obstacles must be overcome, including reductions of the extinction ratio by the misalignment between the polarizer and the detector, grating line width fluctuations, the line edge roughness, etc. This paper reports the authors’ latest achievements in overcoming those problems by solving key technical issues regarding the integration of large-scale polarizers onto the chips of FPAs with individual indium gallium arsenide/indium phosphide (InGaAs/InP) sensors as the basic building blocks. Polarimetric and photovoltaic chips with divisions of the focal plane of 540 × 4 pixels and 320 × 256 superpixels have been successfully manufactured. Polarimetric imaging with enhanced contrast has been demonstrated. The progress made in this work has opened up a broad avenue toward industrialization of high quality polarimetric imaging in infrared wavelengths.
Research on the selection and layout of the cantilever sensor based on photoacoustic spectroscopy gas detection technology
Authors: Cheng Hongtu , Zhang Xiaoxing , Tang Ju , Xiao Song , Mao Shiyi , Wang Dibo , Zhuo Ran
Published: April 2021

Gas detection has become an indispensable part of the power equipment maintenance. Because of many advantages, cantilever enhanced photoacoustic(PA) spectroscopy was studied by many researchers. In this paper, with the help of Finite Element Method (FEM) simulations with the commercial software COMSOL, we have analyzed the distribution of the sound pressure inside the gas cell, in addition, we have analyzed the relationship between the Young’s modulus and size of the cantilever beam and its deformation, the relationship between the cantilever size and its eigen-frequencies were also obtained. Besides, we have performed the experiment of the deformation measurement. The results show that: for the gas cell, when it works at the first order resonance frequency, the maximum value of the sound pressure appears at the geometric center. For the main resonance cavity, with its length and radius increase, the first order resonance frequency of the gas cell decreases. Under the condition of ideal linear sound source, as the length and radius of the main resonance cavity changes, in the frequency domain, the sound pressure response curve changes, the maximum sound pressure corresponds the PA cell with 85 mm in length and 2 mm in radius. For the cantilever beam, with the increase of the Young’s modulus, the deformation decreases. The deformation is proportional to the fourth power of the length, whereas it is inversely proportional to the width and inversely proportional to the third power of the thickness. However, the experimental results showed that there may be a deviation in the vibration measurements by the vibration meter. As for the first order eigen-frequency, it is negatively correlated with the length and positively correlated with the thickness, but independent of the width. With the increase of the distance between the sound source and the cantilever beam, the deformation decreases.
Response of quantum spin networks to attacks
Authors: Sundar Bhuvanesh , Walschaers Mattia , Parigi Valentina , Carr Lincoln D
Published: April 2021

We investigate the ground states of spin models defined on networks that we imprint (e.g., non-complex random networks like Erdos–Renyi, or complex networks like Watts–Strogatz, and Barabasi–Albert), and their response to decohering processes which we model with network attacks. We quantify the complexity of these ground states, and their response to the attacks, by calculating distributions of network measures of an emergent network whose link weights are the pairwise mutual information between spins. We focus on attacks which projectively measure spins. We find that the emergent networks in the ground state do not satisfy the usual criteria for complexity, and their average properties are captured well by a single dimensionless parameter in the Hamiltonian. While the response of classical networks to attacks is well-studied, where classical complex networks are known to be more robust to random attacks than random networks, we find counter-intuitive results for our quantum networks. We find that the ground states for Hamiltonians defined on different classes of imprinted networks respond similarly to all our attacks, and the attacks rescale the average properties of the emergent network by a constant factor. Mean field theory explains these results for relatively dense networks, but we also find the simple rescaling behavior away from the regime of validity of mean field theory. Our calculations indicate that complex spin networks are not more robust to projective measurement attacks, and presumably also other quantum attacks, than non-complex spin networks, in contrast to the classical case. Understanding the response of the spin networks to decoherence and attacks will have applications in understanding the physics of open quantum systems, and in designing robust complex quantum systems—possibly even a robust quantum internet in the long run—that is maximally resistant to decoherence.
Application of candle soot CNPs-TiO2-PVP composite in the detection of volatile organic compounds with aldehyde, amine and ketone functional groups by resistance and impedance responses
Authors: Olifant G E , Kondiah K , Mamo M A
Published: April 2021

We have fabricated a solid-state gas sensor using a composite sensor layer made up of three different sensing materials namely; candle soot Carbon nanoparticles, Titanium dioxide and Poly (vinyl) pyrrolidone (PVP). The study was carried out to study the sensor’s response towards butyraldehyde, diethylamine and isobutyrophenone vapour at room temperature. The sensor was prepared by mixing candle soot CNPs, TiO2 and PVP in dimethylformamide using the ratio (2:1:3) respectively. The sensing materials were characterised using Brunauer–Emmett–Teller (BET), x-ray diffraction (XRD), Transmission and Scanning Electron Microscopy (TEM, SEM). The sensor’s response was measured by injecting a volume of 1 to 5 μl of each liquid analyte in a round-bottomed glass and an LCR metre was used to measure the ∆R and ∆Z responses. In both parameters, the sensor responded well to the different analytes, the response of the sensor linearly increases as the analyte vapour concentration increases. The sensors were discovered to exhibit more sensitivity of 0.07 Ω ppm−1 towards diethylamine in ∆R response and it was more sensitive towards isobutyrophenone in ∆Z response giving a sensitivity of 0.14 Ω ppm−1 while Butyraldehyde had the fastest response time of 145 s and Diethylamine had the fasted recovery time 130 s.
P9 A study to investigate the impact of the COVID-19 pandemic on paediatric cancer patients: an international, multicentre, observational cohort study (COVIDPaedsCancer)
Authors:   Global Children’s NCDs
Published: April 2021

Introduction

Childhood cancers are a leading cause of non-communicable disease deaths for paediatric patients around the world. The COVID-19 pandemic may have impacted on global children’s cancer services, which can have consequences for childhood cancer outcomes. The Global Health Research Group on Children’s Non-Communicable Diseases (Global Children’s NCDs) is currently undertaking the first international study to determine the variation in paediatric cancer management during the COVID-19 pandemic, and the short to medium term impacts on childhood cancer outcomes.

Methods and analysis

This is a multicentre, international, cohort study that will use routinely collected hospital data in a de-identified and anonymised form. Patients will be recruited consecutively into the study, with a 12 -month follow-up period. Patients will be included if they are below the age of 18 years and undergoing anti-cancer treatment for the following cancers: Acute lymphoblastic leukaemia, Burkitt’s Lymphoma, Hodgkin's lymphoma, Wilms Tumour, Sarcoma, Retinoblastoma, Gliomas, Medulloblastomas and Neuroblastomas. Patients must be newly presented or be undergoing active anti-cancer treatment from the 12th March 2020 to the 12th December 2020. The primary objective of the study is to determine 30- and 90-day all-cause mortality rates. This study will examine the factors that influenced these outcomes. Chi-squared analysis will be used to compare mortality between low and middle-income countries and high-income countries. Multilevel, multivariate logistic regression analysis will be undertaken to identify patient-level and hospital-level factors affecting outcomes with adjustment for confounding factors.

Ethics and dissemination

At the host centre, this study was deemed to be exempt from ethical committee approval due to the use of anonymised registry data. At other centres, participating collaborators have gained local approvals in accordance with their institutional ethical regulations. Collaborators will be encouraged to present the results locally, nationally, and internationally. The results will be submitted for publication in a peer reviewed journal.