Arsenic removal by perilla leaf biochar in aqueous solutions and groundwater: An integrated spectroscopic and microscopic examination

Niazi, Nabeel Khan,Bibi, Irshad,Shahid, Muhammad,Ok, Yong Sik,Burton, Edward D.,Wang, Hailong,Shaheen, Sabry M.,Rinklebe, Jö,rg,Lü,ttge, Andreas Elsevier 2018 Environmental pollution Vol.232 No.-

<P><B>Abstract</B></P> <P>In this study, we examined the removal of arsenite (As(III)) and arsenate (As(V)) by perilla leaf-derived biochars produced at 300 and 700 °C (referred as BC300 and BC700) in aqueous environments. Results revealed that the Langmuir isotherm model provided the best fit for As(III) and As(V) sorption, with the sorption affinity following the order: BC700-As(III) > BC700-As(V) > BC300-As(III) > BC300-As(V) (<I>Q</I> <SUB> <I>L</I> </SUB> = 3.85–11.01 mg g<SUP>−1</SUP>). In general, As removal decreased (76–60%) with increasing pH from 7 to 10 except for the BC700-As(III) system, where notably higher As removal (88–90%) occurred at pH from 7 to 9. Surface functional moieties contributed to As sequestration by the biochars examined here. However, significantly higher surface area and aromaticity of BC700 favored a greater As removal compared to BC300, suggesting that surface complexation/precipitation dominated As removal by BC700. Arsenic K-edge X-ray absorption near edge structure (XANES) spectroscopy demonstrated that up to 64% of the added As(V) was reduced to As(III) in BC700- and BC300-As(V) sorption experiments, and in As(III) sorption experiments, partial oxidation of As(III) to As(V) occurred (37–39%). However, XANES spectroscopy was limited to precisely quantify As binding with sulfur species as As<SUB>2</SUB>S<SUB>3</SUB>-like phase. Both biochars efficiently removed As from natural As-contaminated groundwater (As: 23–190 μg L<SUP>−1</SUP>; <I>n</I> = 12) despite in the presence of co-occurring anions (e.g., CO<SUB>3</SUB> <SUP>2−</SUP>, PO<SUB>4</SUB> <SUP>3−</SUP>, SO<SUB>4</SUB> <SUP>2−</SUP>) with the highest levels of As removal observed for BC700 (97–100%). Overall, this study highlights that perilla leaf biochars, notably BC700, possessed the greatest ability to remove As from solution and groundwater (drinking water). Significantly, the integrated spectroscopic techniques advanced our understanding to examine complex redox transformation of As(III)/As(V) with biochar, which are crucial to determine fate of As on biochar in aquatic environments.</P> <P><B>Highlights</B></P> <P> <UL> <LI> BC700 (high temperature) perilla leaf biochar removed more arsenite at pH 7–9 than BC300 (low temperature). </LI> <LI> Langmuir model efficiently delineated sorption affinity for arsenite and arsenate, notably by BC700. </LI> <LI> FTIR spectroscopy and elemental maps indicated arsenic association with surface functional groups. </LI> <LI> XANES spectroscopy revealed redox transformation/fate of arsenite and arsenate on biochars. </LI> <LI> Both biochars depleted arsenic in groundwater, with slightly higher removal by BC700. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

On Multi Query Optimization Algorithms Problem

Muhammad, L. J.,Yahaya Bala Zakariyau,Abdullahi Garba Ali,Abba Garba 보안공학연구지원센터 2014 International Journal of Database Theory and Appli Vol.7 No.6

Without multi query optimization, Relational Database Management System for online and analytical decision support systems would have been inefficient and hence unpractical. It is an expensive process because it relies at a great extent on evaluating the different plans (access paths) and choosing an optimal one among them. In Multi Query Optimization, queries are executed in batches and there were many different algorithms acted in such way that, in case some queries have a common sub-expression such a sub- expression is executed once and the output shared. We studied the basic multi query optimization algorithms including Basic Volcano, Volcano-SH and Volcano RU, identified their strengths and weaknesses and recommend strategies for developing new improved multi query optimization algorithm so as to reduce weaknesses and integrate strengths of the different basic multi query algorithms into one efficient algorithm.

Multi Query Optimization Algorithm Using Semantic and Heuristic Approaches

L. J. Muhammad,Abdullahi Garba Ali,Yahaya Bala Zakariyau,Ibrahim A. Mohammed 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.6

Multi Query Optimization is one of the most important tasks in Relational Database Management System (RBMS) and it becomes common due to high usage of online decision support management systems in every industry nowadays. In multi query optimization, queries are optimized and executed in batches. However, there are many algorithms use to detect and unified common sub-expressions among multiple queries and unified them so that the more encompassing sub- expression is executed and the other sub-expressions are derived from. In this work, multi-query optimization algorithm using heuristics and semantic approaches was proposed and encoded on SQL Server version 10.0.1600 and three queries were used for the experiment between the proposed algorithm and most recent basic Multi Query Optimization Algorithm (Volcano RU). The result of experiment showed that, Proposed Algorithm gave the best plans compared Volcano RU Algorithm, across all three queries and was best for all queries in terms of execution time and CPU time.

Security Challenges for Building Knowledge-Based Economy in Nigeria

L. J. Muhammad,Abdullahi Garba Ali,Ibrahim Sani Iliya 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.1

The world economy is changing at an unprecedented rate. The forces of globalization and Information and Communication Technologies (ICT) progress are changing the way people all over the world living. Some countries, especially in the emerging world such as China, Malaysia, India, and Singapore among others, are using this wave of change to drive rapid growth in their economies. Nigeria yet to struggle to come to terms with these fundamental shifts in the global economic order. And for it (Nigeria) to secure its place in the global economy, it needs at least a decade to balance the growth that lays the foundation of this ongoing prosperity. This balanced growth can only come from one place, thus the knowledge based economy. Hence, to build the Knowledge-Based Economy in Nigeria, the security challenges of the phenomena (Knowledge-Based Economy) need to be identified and its possible solutions. This paper presents some of the security challenges for building Knowledge-Based Economy in Nigeria and their possible remedies.

Efficient Algorithm for Multi Query Optimization

L. J. Muhammad,Yahaya Bala Zakariyau,Abdullahi Garba Ali 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.6

Multi Query Optimization is an important process in database and it becomes the commonplace due to the frequent usage of decision support systems in almost all the multinational enterprises. The multiple queries from different users that have been addressed to one schema often have a lot of common sub-expressions and it is the function of the multi query optimization algorithms such as Basic Volcano, Volcano RU and Volcano SH algorithms to optimize such multiple queries together and executes the common operation once and share the output among the queries. In this work, a multi query shareability algorithm which can efficiently detect the common sub- expressions among the multiple queries and share the output among those queries was proposed and algorithm for optimal order of those queries was also proposed. The Algorithm has a time complexity of O(n2 + 9n +6) while the most recent basic algorithm thus Volcano RU Algorithm has O(2n2 +20n +12), both the algorithms have O(n2) time complexity which is quadratic in nature. However, the Proposed Algorithm is more efficient and better than Volcano RU algorithm even if n approach to infinity.

SYNTHESIS, CHARACTERISTICS AND APPLICATIONS OF ZnO NANOWIRES IN DYE-SENSITIZED SOLAR CELLS VIA WATER BATH METHOD

MUHAMMAD SALEEM,M. ASHFAQ AHMAD,RIZWAN RAZA,S. J. XUE,L. FANG,F. WU,W. J. LI,C. L. XU,L. HU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.6

Zinc oxide (ZnO) nanowire (NW) ¯lms were synthesized at low temperature (95?C) throughamine-assisted solution process and used as photoanode for the fabrication of dye-sensitized solarcells (DSSCs). It was found that with the addition of polyethyleneimine (PEI) and ammoniumhydroxide (NH 4 OH) in growth solution, the NWs were smaller in diameter and longer in lengthby prolonging the growth time without refreshing the growth solution. A reasonable overallconversion e±ciency of 1.25% was achieved with photoanode based on ZnO NWs containing PEIand NH 4 OH. However, DSSC fabricated with ZnO NWs not containing PEI and NH 4 OH showedlow conversion e±ciency of 0.58%. All the DSSCs exhibited almost similar values of open circuitvoltage ( V OC) and ¯ll factor (FF). Interestingly, DSSC based on ZnO NWs with PEI and NH 4 OHobtained two times higher short circuit current density ( J SC) compared to ZnO NWs photoanodewithout PEI and NH 4 OH. The increase in e±ciency and J SC with the length of NWs is attributedto the increase in internal surface area for su±cient dye loading and light harvesting.

Arsenic removal by Japanese oak wood biochar in aqueous solutions and well water: Investigating arsenic fate using integrated spectroscopic and microscopic techniques

Niazi, Nabeel Khan,Bibi, Irshad,Shahid, Muhammad,Ok, Yong Sik,Shaheen, Sabry M.,Rinklebe, Jö,rg,Wang, Hailong,Murtaza, Behzad,Islam, Ejazul,Farrakh Nawaz, M.,Lü,ttge, Andreas Elsevier 2018 Science of the Total Environment Vol.621 No.-

<P><B>Abstract</B></P> <P>In this study, we examined the sorption of arsenite (As(III)) and arsenate (As(V)) to Japanese oak wood-derived biochar (OW-BC) in aqueous solutions, and determined its efficiency to remove As from As-contaminated well water. Results revealed that, among the four sorption isotherm models, Langmuir model showed the best fit to describe As(III) and As(V) sorption on OW-BC, with slightly greater sorption affinity for As(V) compared to As(III) (<I>Q<SUB>L</SUB> </I> =3.89 and 3.16mgg<SUP>−1</SUP>; R<SUP>2</SUP> =0.91 and 0.85, respectively). Sorption edge experiments indicated that the maximum As removal was 81% and 84% for As(III)- and As(V)-OW-BC systems at pH7 and 6, respectively, which decreased above these pH values (76–69% and 80–58%). Surface functional groups, notably OH, COOH, CO, CH<SUB>3</SUB>, were involved in As sequestration by OW-BC, suggesting the surface complexation/precipitation and/or electrostatic interaction of As on OW-BC surface. Arsenic K-edge X-ray absorption near edge structure (XANES) spectroscopy indicated that 36% of the added As(III) was partially oxidized to As(V) in the As(III) sorption experiment, and in As(V) sorption experiment, 48% of As(V) was, albeit incompletely, reduced to As(III) on OW-BC surface. Application of OW-BC to As-contaminated well water (As: 27–144μgL<SUP>−1</SUP>; <I>n</I> =10) displayed that 92 to 100% of As was depleted despite in the presence of co-occurring competing anions (e.g., SO<SUB>4</SUB> <SUP>2−</SUP>, CO<SUB>3</SUB> <SUP>2−</SUP>, PO<SUB>4</SUB> <SUP>3−</SUP>). This study shows that OW-BC has a great potential to remove As from solution and drinking (well) water. Overall, the combination of macroscopic sorption data and integrated spectroscopic and microscopic techniques highlight that the fate of As on biochar involves complex redox transformation and association with surface functional moieties in aquatic systems, thereby providing crucial information required for implication of biochar in environmental remediation programs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Arsenic removal efficiency of Japanese oak wood biochar (OW-BC) was explored. </LI> <LI> Langmuir model provided the best fit, with a greater <I>Q<SUB>L</SUB> </I> for arsenate than arsenite. </LI> <LI> XANES spectroscopy indicated redox transformation of arsenite⇔arsenate on OW-BC. </LI> <LI> FTIR spectra revealed arsenite/arsenate association with functional groups on OW-BC. </LI> <LI> OW-BC efficiently removed As (92 to 100%) from drinking well water. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

경량 고강도 친환경 복합재 제조를 위한 나노셀룰로오스 장섬유의 연속 제조 및 공정 설계

김현찬(H. C. Kim),푸자(P. S. Panicker),주심옥(Q. Y. Zhu),라티프(L. Muhammad),김재환(J. Kim) Korean Society for Precision Engineering 2019 한국정밀공학회 학술발표대회 논문집 Vol.2019 No.10월