bluuebunny/crossref_metadata_2025 huggingface dataset:
On the complex role of ammonia in the electroless deposition of curved silver patches on silica nanospheres
Authors: Sadafi Fabrizio-Zagros , Sauerbeck Christian , Braunschweig Björn , Klupp Taylor Robin N.
Published: September 2018

Surface conformal growth of silver on colloidal silica is mediated by silver–ammonia complexation and ammonia–silica hydrogen bonding.
Hybrid materials based on transition metal–BTC–benzimidazole: solvent assisted crystallographic and structural switching
Authors: Tiwari Ranjay K. , Behera J. N.
Published: September 2018

Five transition metal–BTC–BIm based coordination polymers with hierarchical structures were synthesized under hydro/solvothermal condition. Crystal structure analysis of the compounds showed that 1 forms a 1D chain, 2 and 3 have 2D layers, while 4 and 5 have three-dimensional architectures.
Forcing the ‘lazy’ protons to work
Authors: Duong Nghia Tuan , Yarava Jayasubba Reddy , Trébosc Julien , Nishiyama Yusuke , Amoureux Jean-Paul
Published: September 2018

In natural abundance samples, less than 1% of the protons collaborate with CPMAS transfers. With the flip-back method and RFDR decoupling (FB-RFDR), all protons cooperate for the transfers, even the ‘lazy ones’.
Excitonic phenomena in perovskite quantum-dot supercrystals
Authors: Vovk Ilia A. , Tepliakov Nikita V. , Baimuratov Anvar S. , Leonov Mikhail Yu. , Baranov Alexander V. , Fedorov Anatoly V. , Rukhlenko Ivan D.
Published: September 2018

The paper presents a first theory of Frenkel excitons in two-dimensional lead halide perovskite quantum-dot supercrystals.
Ruthenium complexes featuring cooperative phosphine–pyridine–iminophosphorane (PNN) ligands: synthesis, reactivity and catalytic activity
Authors: Cheisson Thibault , Mazaud Louis , Auffrant Audrey
Published: September 2018

Ruthenium complexes with an iminophosphorane based (PNN) ligand; the NP substituent influences the coordination and the reactivity of the formed complexes.
Monolithic heterojunction quasi-solid-state battery electrolytes based on thermodynamically immiscible dual phases
Authors: Cho Sung-Ju , Jung Gwan Yeong , Kim Su Hwan , Jang Minchul , Yang Doo-Kyung , Kwak Sang Kyu , Lee Sang-Young
Published: September 2018

Monolithic heterojunction quasi-solid-state battery electrolytes (MH-QEs) based on thermodynamically immiscible dual phases are presented as an electrode-customized multifunctional electrolyte.
Rational design of polyaromatic ionomers for alkaline membrane fuel cells with >1 W cm−2 power density
Authors: Maurya Sandip , Noh Sangtaik , Matanovic Ivana , Park Eun Joo , Narvaez Villarrubia Claudia , Martinez Ulises , Han Junyoung , Bae Chulsung , Kim Yu Seung
Published: September 2018

High-performance of polyaromatic alkaline membrane fuel cells was achieved with a polyfluorene ionomer with minimizing adsorption on hydrogen oxidation catalysts.
Development of a [68Ga]-ghrelin analogue for PET imaging of the ghrelin receptor (GHS-R1a)
Authors: Charron C. L. , McFarland M. S. , Dhanvantari S. , Luyt L. G.
Published: September 2018

A 68Ga-labelled ghrelin(1-19) analogue is described as a high affinity peptide for ghrelin receptor PET imaging using a sequence derived directly from the endogenous ligand, yet modified for improved stability.
Direct ink writing of organic and carbon aerogels
Authors: Chandrasekaran Swetha , Yao Bin , Liu Tianyu , Xiao Wang , Song Yu , Qian Fang , Zhu Cheng , Duoss Eric B. , Spadaccini Christopher M. , Li Yat , Worsley Marcus A.
Published: September 2018

Additive manufacturing is used to overcome inherent aerogel limitations. 3D printed aerogels simultaneously exhibit large capacitance and fast ion transport in millimeter-thick electrodes.
Robust determination of differential abundance in shotgun proteomics using nonparametric statistics
Authors: Slama Patrick , Hoopmann Michael R. , Moritz Robert L. , Geman Donald
Published: September 2018

A peptide-centric, non-parametric algorithm to quantify protein abundance between conditions from shotgun proteomics.
4-Cyanopyridine-catalyzed anti-Markovnikov selective hydroboration of alkenes
Authors: Xu Rui , Lu Guo-ping , Cai Chun
Published: September 2018

4-Cyanopyridine catalyzed anti-Markovnikov selective hydroboration of alkenes with B2pin2 affords the corresponding alkylboronates in good yields via a radical pathway.
Holey single-walled carbon nanotubes for ultra-fast broadband bolometers
Authors: Kopylova Daria S. , Fedorov Fedor S. , Alekseeva Alena A. , Gilshteyn Evgenia P. , Tsapenko Alexey P. , Bubis Anton V. , Grebenko Artem K. , Popov Zakhar I. , Sorokin Pavel B. , Gladush Yuriy G. , Anisimov Anton S. , Nasibulin Albert G.
Published: September 2018

A holey carbon nanotube network is designed to improve the performance of bolometers. The material possesses a temperature coefficient of resistance up to −2.8% K−1.
Novel binaphthyl and biphenyl α- and β-amino acids and esters: organocatalysis of asymmetric Diels–Alder reactions. A combined synthetic and computational study
Authors: Bulman Page Philip C. , Kinsey Francesca S. , Chan Yohan , Strutt Ian R. , Slawin Alexandra M. Z. , Jones Garth A.
Published: September 2018

Asymmetric catalysis of the Diels–Alder reaction between cyclopentadiene and cinnamaldehydes has been studied using as catalysts a range of novel α- and β-aminoacids and aminoesters with binaphthyl and biphenyl backbones.
An efficient lactone-to-lactam conversion for the synthesis of thiophene Pechmann lactam and the characterization of polymers thereof
Authors: Lee Kyu Cheol , Lee Hae Rang , Kang So-Huei , Lee Jungho , Park Young IL , Noh Seung Man , Oh Joon Hak , Yang Changduk
Published: September 2018

We proposed an efficient methodology for Pechmann lactone-to-lactam conversion for various molecular applications.
Heteropore covalent organic frameworks: a new class of porous organic polymers with well-ordered hierarchical porosities
Authors: Liang Rong-Ran , Zhao Xin
Published: September 2018

This review highlights the development of heteropore covalent organic frameworks, a new class of porous organic polymers which exhibit well-ordered heterogeneous/hierarchical porosities.
Direct thiolation of aza-heteroaromatic N-oxides with disulfides via copper-catalyzed regioselective C–H bond activation
Authors: Lai Miao , Zhai Ke , Cheng Chuance , Wu Zhiyong , Zhao Mingqin
Published: September 2018

A novel and efficient thiolation reaction of aza-heteroaromatic N-oxides with disulfides via copper catalyzed C–H activation has been developed.
Engaging 2-methyl indolenines in a tandem condensation/1,5-hydride transfer/cyclization process: construction of a novel indolenine–tetrahydroquinoline assembly
Authors: Liu Siyuan , Zhang Wenzhu , Qu Jingping , Wang Baomin
Published: September 2018

An efficient BF3·Et2O-catalyzed diastereoselective tandem condensation/1,5-hydride transfer/cyclization strategy for the synthesis of a novel indolenine–tetrahydroquinoline assembly was reported.
Cobalt-catalyzed radical cyclization of isocyanides forming phenanthridine derivatives
Authors: Liu Xiangyu , Wu Chengjuan , Zhang Jing , Shi Yihan , Zhang Shengnan , Geng Yan , Tung Chen-Ho , Wang Wenguang
Published: September 2018

A neutral cobalt(ii) compound catalyzes the radical cyclization of 2-isocyano-biphenyls with various alkyl halides, providing a series of phenanthridine-fused polycycles.
Metal- and photocatalyst-free visible-light-promoted regioselective selenylation of coumarin derivatives via oxidation-induced C–H functionalization
Authors: Yang Daoshan , Li Guoqing , Xing Chengyu , Cui Wenwen , Li Kexin , Wei Wei
Published: September 2018

A visible-light-promoted approach for the regioselective selenylation of 4-amino substituted coumarins has been initially realized under metal- and photocatalyst-free conditions at room temperature.
Total synthesis of (−)-8-epi-chromazonarol enabled by a unique N2H4·H2O promoted intramolecular oxa-Michael cyclization reaction
Authors: Liu Lin , Song Huayue , Chen Peng , Yuan Ziyun , Feng Shangbiao , Zhang Weiwei , Fang Bowen , Xie Xingang , She Xuegong
Published: September 2018

The first enantioselective synthesis of 8-epi-chromazonarol was achieved by a N2H4·H2O promoted highly diastereoselective oxa-Michael cyclization reaction.
Gold-catalyzed ring enlargement and cycloisomerization of alkynylamide tethered alkylidenecyclopropanes
Authors: Zhang Jia-hao , Wei Yin , Shi Min
Published: September 2018

A gold(i)-catalyzed ring enlargement and cycloisomerization of alkynylamide tethered alkylidenecyclopropanes has been developed, providing facile access to functionalized polycyclic and spiropolycyclic products based on the use of gold(i) catalysts.
Collateral hydrogenation over proton-conducting Ni/BaZr0.85Y0.15O3−δ catalysts for promoting CO2 methanation
Authors: Choi Sungjun , Choi Sung Min , Yoon Kyung Joong , Son Ji-Won , Lee Jong-Ho , Kim Byung-Kook , Sang Byoung-In , Kim Hyoungchul
Published: September 2018

A novel steam hydrogenation process is demonstrated by applying collateral CO2 methanation over Ni/BaZr0.85Y0.15O3−δ, which outperforms its conventional Ni/Al2O3 counterpart.
Functionalized carboxylate deposition of triphenylamine-based organic dyes for efficient dye-sensitized solar cells
Authors: Mamun Md Ataul , Qiao Qiquan , Logue Brian A.
Published: September 2018

Functionalized carboxylate deposition involves deposition of molecules from the gas phase and is an alternative dye loading technique to dip-coating. It was used to create a monolayer of large molecular weight dyes on TiO2, providing multiple advantages to dip-coating.
Protonated glycine supramolecular systems: the need for quantum dynamics
Authors: Gabas Fabio , Di Liberto Giovanni , Conte Riccardo , Ceotto Michele
Published: September 2018

Quantum mechanical simulations unequivocally explain experimental IR spectra of protonated supramolecular systems.
3D printing of complex origami assemblages for reconfigurable structures
Authors: Zhao Zeang , Kuang Xiao , Wu Jiangtao , Zhang Qiang , Paulino Glaucio H. , Qi H. Jerry , Fang Daining
Published: September 2018

Digital light processing-based 3D printing is utilized to fabricate complex 3D reconfigurable origami structures. These origami assemblages can be directly created by one-step printing of the customized photocurable elastomer.
Narrow bandgap semiconductor decorated wood membrane for high-efficiency solar-assisted water purification
Authors: Liu Hanwen , Chen Chaoji , Wen Huang , Guo Ruixue , Williams Nick A. , Wang Baodui , Chen Fengjuan , Hu Liangbing
Published: September 2018

The solar evaporator combining narrow bandgap semiconductor nanoparticles with wood substrate exhibits high efficiency for sea water desalination.
Favorable lithium deposition behaviors on flexible carbon microtube skeleton enable a high-performance lithium metal anode
Authors: Sun Changzhi , Wu Tian , Wang Jianing , Li Wenwen , Jin Jun , Yang Jianhua , Wen Zhaoyin
Published: September 2018

Favorable lithium deposition behaviors were investigated on FCMS for a high-performance Li metal anode.
Preventing diatom adhesion using a hydrogel with an orthosilicic acid analog as a deceptive food
Authors: Chen Weipeng , Hao Dezhao , Guo Xinglin , Hao Wanjun , Jiang Lei
Published: September 2018

With the development of technology and society, ocean development is becoming more and more necessary and frequent.
Hierarchical nanostructure-tuned super-high electrochemical stability of nickel cobalt sulfide
Authors: Li Yanhong , Liu Hao , Xu Jü , Liu Yuanyuan , Wang Meiri , Li Jing , Cui Hongtao
Published: September 2018

The super-high electrochemical cycling stability of NiCo2S4 as an electrode material for supercapacitors is obtained by tuning its hierarchical structure.
The synthesis, characterization and electrochemical performance of hollow sandwich microtubules composed of ultrathin Co3O4 nanosheets and porous carbon using a bio-template
Authors: Sun Dongya , He Liwen , Chen Rongqiang , Lin Zhenyong , Lin Shanshan , Xiao Caixia , Lin Bizhou
Published: September 2018

Biomorphic composites exhibit remarkable electrochemical performance, due to the 2D nanosheets supported on porous carbon tubes inherited from the biotemplate.
MoS2/CQDs obtained by photoreduction for assembly of a ternary MoS2/CQDs/ZnIn2S4 nanocomposite for efficient photocatalytic hydrogen evolution under visible light
Authors: Wang Bingqing , Deng Zirong , Fu Xianzhi , Li Zhaohui
Published: September 2018

Photoreduction of (NH4)2MoS4 over CQDs to obtain MoS2/CQDs for assembly of ternary MoS2/CQDs/ZnIn2S4 with superior photocatalytic activity for hydrogen evolution.
Substrate-inactivated cyclooxygenase-2 is disposed of by exosomes through the ER–Golgi pathway
Authors: Saadi Esraa , Tal Sharon , Barki-Harrington Liza
Published: September 2018

Catalysis of arachidonic acid (AA) by cyclooxygenase-2 (COX-2) gives rise to a single product that serves as a precursor for all prostaglandins, which are central mediators of inflammation. Rapid up-regulation of COX-2 expression in response to pro-inflammatory stimuli is a well-characterized means of generating the large pool of prostaglandins necessary for inflammation. However, an efficient inflammatory process must also terminate rapidly and thus requires cessation of COX-2 enzymatic activity and removal of excess protein from the cell. Previous studies showed that COX-2 that has not been exposed to AA (‘naive’) degrades in the cellular proteasome. However, continuous exposure to AA induces suicide inactivation of COX-2 and its elimination no longer occurs in neither the proteasomal nor lysosomal machineries. In the present study, we show that either overexpressed or endogenously induced COX-2 is secreted via exosomes through the endoplasmic reticulum–Golgi pathway. We further find that excretion of COX-2 is significantly enhanced by prolonged exposure to AA. Genetic or chemical inhibition of COX-2 enzymatic activity has no effect on its secretion in the absence of substrate, but prevents the additional activity-dependent secretion. Finally, transfer of COX-2 to target cells only occurs in the absence of AA stimulation. Together, these results suggest that exosomal secretion of AA-activated COX-2 constitutes a means to remove damaged inactive COX-2 from the cell.
Non-coding RNA in drug resistance of hepatocellular carcinoma
Authors: Ding Bisha , Lou Weiyang , Xu Liang , Fan Weimin
Published: September 2018

Hepatocellular carcinoma (HCC) has been one of the most highly lethal cancers. The acquisition of drug resistance accounts for the majority of poor effects of chemotherapy in HCC. Non-coding RNAs (ncRNAs) including miRNAs, long ncRNAs (lncRNAs), and circular RNA (circRNA) have been well-documented to participate in cancer occurrence and progression. Recently, multiple studies have highlighted the key roles of ncRNAs in chemoresistance of HCC. In addition, accumulating evidence has demonstrated that they can serve as biomarkers in diagnosis, treatment, and prognosis of HCC. In this review, we first overviewed up-to-date findings regarding miRNA and lncRNA in drug resistance of HCC, then summarized specific mechanisms that they modulate chemoresistance of HCC, and finally discussed their potential clinical application in overcoming the obstacle of HCC chemoresistance in the future.
Urinary angiotensinogen predicts progressive chronic kidney disease after an episode of experimental acute kidney injury
Authors: Cui Shuang , Wu Liling , Feng Xiaodan , Su Huanjuan , Zhou Zhanmei , Luo Weihong , Su Cailing , Li Yajing , Shi Meng , Yang Zhichen , Cao Wei
Published: September 2018

One of the major obstacles to prevent AKI-CKD transition is the lack of effective methods to follow and predict the ongoing kidney injury after an AKI episode. In the present study, we test the utility of urinary angiotensinogen (UAGT) for dynamically evaluating renal structural changes and predicting AKI-CKD progression by using both mild and severe bilateral renal ischemia/reperfusion injury mice. UAGT returns to pre-ischemic levels 14 days after mild AKI followed by kidney architecture restoration, whereas sustained increase in UAGT accompanies by ongoing renal fibrosis after severe AKI. UAGT at day 14–42 correlates with renal fibrosis 84 days after AKI. For predicting fibrosis at day 84, the area under receiver operating characteristics curve of UAGT at day 14 is 0.81. Persistent elevation in UAGT correlates with sustained activation of intrarenal renin–angiotensin system (RAS) during AKI-CKD transition. Abrogating RAS activation post AKI markedly reduced renal fibrosis, with early RAS intervention (from 14 days after IRI) more beneficial than late intervention (from 42 days after IRI) in alleviating fibrosis. Importantly, UAGT decreases after RAS intervention, and its level at day 14–28 correlates with the extent of renal fibrosis at day 42 post RAS blockade. A pilot study conducted in patients with acute tubular necrosis finds that compared with those recovered, patients with AKI-CKD progression exhibits elevated UAGT during the 3-month follow-up after biopsy. Our study suggests that UAGT enables the dynamical monitoring of renal structural recovery after an AKI episode and may serve as an early predictor for AKI-CKD progression and treatment response.
Anisotropic turbulent transport in stably stratified rotating stellar radiation zones
Authors: Mathis S. , Prat V. , Amard L. , Charbonnel C. , Palacios A. , Lagarde N. , Eggenberger P.
Published: September 2018

Context. Rotation is one of the key physical mechanisms that deeply impact the evolution of stars. Helio- and asteroseismology reveal a strong extraction of angular momentum from stellar radiation zones over the whole Hertzsprung–Russell diagram.

Aims. Turbulent transport in differentially rotating, stably stratified stellar radiation zones should be carefully modelled and its strength evaluated. Stratification and rotation imply that this turbulent transport is anisotropic. So far only phenomenological prescriptions have been proposed for the transport in the horizontal direction. This, however, constitutes a cornerstone in current theoretical formalisms for stellar hydrodynamics in evolution codes. We aim to improve its modelling.

Methods. We derived a new theoretical prescription for the anisotropy of the turbulent transport in radiation zones using a spectral formalism for turbulence that takes simultaneously stable stratification, rotation, and a radial shear into account. Then, the horizontal turbulent transport resulting from 3D turbulent motions sustained by the instability of the radial differential rotation is derived. We implemented this framework in the stellar evolution code STAREVOL and quantified its impact on the rotational and structural evolution of solar metallicity low-mass stars from the pre-main-sequence to the red giant branch.

Results. The anisotropy of the turbulent transport scales as N4τ2/(2Ω2), N and Ω being the buoyancy and rotation frequencies respectively and τ a time characterizing the source of turbulence. This leads to a horizontal turbulent transport of similar strength in average that those obtained with previously proposed prescriptions even if it can be locally larger below the convective envelope. Hence the models computed with the new formalism still build up too steep internal rotation gradients compared to helioseismic and asteroseismic constraints. As a consequence, a complementary transport mechanism such as internal gravity waves or magnetic fields is still needed to explain the observed strong transport of angular momentum along stellar evolution.

Conclusions. The new prescription links for the first time the anisotropy of the turbulent transport in radiation zones to their stratification and rotation. This constitutes important theoretical progress and demonstrates how turbulent closure models should be improved to get firm conclusions on the potential importance of other processes that transport angular momentum and chemicals inside stars along their evolution.
It’s hydrogeology but not as we know it: Sub-seafloor groundwater flow driven by thermal gradients
Authors: Desens A. , Post V.E.A. , Houben G.J. , Kuhn T. , Walther M. , Graf Thomas
Published: September 2018

Groundwater flow beneath the oceans plays an important role for cooling the earth’s crust and geochemical cycles, yet it remains an understudied subject in hydrogeology. This contribution focuses on the circulation of seawater through basalt covered by deep-sea sediments in the equatorial northeast Pacific Ocean. Numerical model simulations are used to infer the factors controlling the flow patterns that develop between basalt outcrops. The energy to drive the flow is derived from the crustal heat flux. It is found that the sediment thickness plays a key role in determining the development of hydrothermal siphons, i.e. the flow between two adjacent seamounts where one acts as a recharge point and the other as a discharge point for seawater. Amongst the various factors tested, the outcrop width was an important factor as well.
Spreading of brine in the Puck Bay in view of in-situ measurements
Authors: Robakiewicz Małgorzata
Published: September 2018

Since autumn of 2010 in the north-eastern part of Poland underground gas stores are under construction by diluting salt deposits. A by-product of the technology applied is brine, which is discharged into the coastal waters of the Puck Bay (south Baltic Sea). In the pre-investment study a theoretical analysis of the mixing conditions in the near-field and far-field of the proposed installation was conducted. An extensive monitoring programme carried out since 2010 shows a good mixing of brine with the surrounding waters. Excess salinity due to the continuous discharge of brine estimated using data measured in situ is generally lower than permitted, i.e. not exceeding 0.5 psu in the near-field of installation.
Comparison of manually and automatically derived fresh-saline groundwater boundaries from helicopter-borne EM data at the Jade Bay, Northern Germany
Authors: Siemon Bernhard , Steuer Annika , Deus Nico , Elbracht Jörg
Published: September 2018

The Federal Institute for Geosciences and Natural Resources (BGR) conducted many airborne geophysical surveys in Northern Germany during the last decades. The coastal regions of Lower Saxony were investigated by frequency-domain helicopter-borne electromagnetics (HEM) to reveal the bulk resistivity of the subsurface (sediments and pore fluids). The State Authority for Mining, Energy and Geology (LBEG) is preparing a statewide “saltwater map” for Lower Saxony with a focus on the coastal aquifers influenced by seawater intrusion. For this purpose, the HEM resistivities are used in combination with groundwater data and a geological model to derive the lower fresh-water boundary. As appropriate depth values are manually picked from vertical resistivity sections, this procedure is time consuming. Therefore, we tested an alternative, which automatically derives the fresh-saline groundwater boundary directly from the HEM resistivity models. The ambiguity between brackish/saline water and clayey sediments as source for low resistivities can somewhat be reduced by the application of gradients instead of threshold values for searching an appropriate boundary. We compare results of both methods using a dataset from a coastal region at the Jade Bay.
Hydrogeological structures as burried valley along the Eastern Pomerania Polish coast of the Baltic Sea
Authors: Szelewicka Anna
Published: September 2018

One of the characteristic feature of geological structure of the southern Baltic coast is presence of deep structures in Pleistocene sediments. Meaning of deep aquifers is unmeasurably important for water economy. The water bearing structures are situated in substantial depth and are better isolated from the surface than the water of shallow aquifers. It has important meaning for natural protection of these waters. Water resource of the structure is substantially increase in case when in water drainage zone where regional and local water circulation are focused. Simultaneously hydrogeological parameters of Pleistocene strata in the frame of deep structure are considerably advantageous rather than parameters of deeper aquifers.
A thruster using magnetic reconnection to create a high-speed plasma jet
Authors: Bathgate Stephen N. , Bilek Marcela M.M. , Cairns Iver H. , McKenzie David R.
Published: September 2018

Plasma thrusters propel spacecraft by the application of Lorentz forces to ionized propellants. Despite evidence that Lorentz forces resulting from magnetic reconnection in solar flares and Earth's magnetopause produce jets of energetic particles, magnetic reconnection has only recently been considered as a means of accelerating plasma in a thruster. Based on theoretical principles, a pulsed magnetic reconnection thruster consisting of two parallel-connected slit coaxial tubes was constructed. The thruster was operated in argon plasma produced by RF energy at 13.56 MHz. A 1.0 ms current pulse of up to 1500 A was applied to the tubes. Three results provide evidence for magnetic reconnection. (1) The production of high-energy electrons resembling the outflow that is observed in the reconnection of field lines in solar flares and in laboratory experiments. (2) The high-energy electron current coincided with the rise of the magnetic field in the thruster and was followed by a large ion current. (3) In accordance with known physics of magnetic reconnection, ion currents were found to increase as the plasma became less collisional. The Alfvén speed of the outflowing ions was calculated to be 8.48 × 103 m s−1corresponding to anIspof 860 s.
Polyelectrolytes and small angle scattering
Authors: Combet Jérôme
Published: September 2018

We present an introduction to the application of small angle Xray and neutron scattering to the study of polyelectrolyte solutions. We aim to give a simple overview of the structural information that can be gained with these techniques. In particular, we show how neutron scattering associated to isotopic labelling enables the determination of the different partial structure functions as well as the dispersion state and the average conformation of polyions.
Modelling of Tsunami Due to Submarine Landslide by Smoothed Particle Hydrodynamics Method
Authors: Huan Vo Nguyen Phu , Harahap Indra Sati H. , Alaloul Wesam Salah
Published: September 2018

Submarine landslide is the most serious threat on both local and regional scales. By way of addition to destroying directly offshore structures, slope failures may also generate destructive tsunami waves. This study has developed a numerical model based on the Smoothed Particle Hydrodynamics (SPH) method to predict four stages of generation, propagation, run-up, and impact of tsunami phenomenon. The numerical predictions in the research were validated with results in the literature and experimental tests. The results of the physical and numerical results presented in this study effort to develop these rule of thumbs to clearly understand some of the mechanics that may play a role in the assessment of tsunami waves.
Comparison of Various Spectral Models for the Prediction of the 100-Year Design Wave Height
Authors: Ahmad Sayyid Zainal Abidin Syed , Husain Mohd Khairi Abu , Zaki Noor Irza Mohd , Mohd Mohd Hairil , Najafian Gholamhossein
Published: September 2018

Offshore structures are exposed to random wave loading in the ocean environment, and hence the probability distribution of the extreme values of their response to wave loading is required for their safe and economical design. In most cases, the dominant load on offshore structures is due to wind-generated random waves where the ocean surface elevation is defined using appropriate ocean wave energy spectra. Several spectral models have been proposed to describe a particular sea state that is used in the design of offshore structures. These models are derived from analysis of observed ocean waves and are thus empirical in nature. The spectral models popular in the offshore industry include Pierson-Moskowitz spectrum and JONSWAP spectrum. While the offshore industry recognizes that different methods of simulating ocean surface elevation lead to different estimation of design wave height, no systematic investigation has been conducted. Hence, the aim of this study is to investigate the effects of predicting the 100-year responses from various wave spectrum models. In this paper, the Monte Carlo time simulation (MCTS) procedure has been used to compare the magnitude of the 100-year extreme responses derived from different spectral models. Additionally, the linear random wave theory (LRWT) was implemented to simulate the offshore structural responses due to random wave loading. The models have been tested for three different environmental conditions represented by Hs = 15m, 10m and 5m respectively. The accuracy of the predictions of the 100-year responses from Pierson-Moskowitz and JONSWAP spectrums will then be investigated.
The Framework for Effective Human Resource Management at Construction Site
Authors: Othman Idris , Hashim Zain , Mohamad Hisham , Napiah Madzlan
Published: September 2018

Human resource management framework being one of the issue across global construction industries. It is a major concern in the construction industry because inefficiency, delay and cost from construction work could be affected and causing great losses to individuals and organizations. Therefore, resource management framework is changing the way resource management can be approached. Most of the construction companies around the world are implementing human resource management systems to reduce cost, eliminate delaying project, and to provide an efficient framework in their construction site. The objective of this paper is to investigate the effectiveness of implementing human resource management framework in construction site. The methodology included is a combination of literature review, market studies and detailed questionnaire survey before starting the actual survey, a pilot study for this questionnaire was done, which confirms its acceptance. Based on findings from the researcher, most of the company and contractor firms have awareness about management of resource at construction site as human resource management is a major concern on construction industries.
Variety of Accident Causes in Construction Industry
Authors: Othman Idris , Majid Rafe , Mohamad Hisham , Shafiq Nasir , Napiah Madzlan
Published: September 2018

Construction Industry is a high risk industry and widely recognised as one of most hazardous occupation in the world. The statistic of accidents in Malaysia give us a picture that Malaysian construction industry is one of the dangerous sectors that need a drastic overhaul from the current site safety practices. This paper describes a review of the accident causes occurred in construction site by various researchers during the last twenty (20) years. This paper discusses the accident causes in Malaysia construction works and entire world. The data collected shows that variety of accident causes in construction industry either in Malaysia or other country.
Framework Development Methodology for Sustainable Procurement of Construction Works in Indonesia
Authors: Abduh Muhamad , Wirahadikusumah Reini D. , Messah Yunita
Published: September 2018

To implement sustainable development in construction sector, or called as sustainable construction, Indonesian still face challenges that requires massive research and developments related to that issue. One of the most important practices in sustainable construction is adoption of sustainable principle in procurement processes or called sustainable procurement. This paper will discuss a methodology formulation that is designed to develop a framework for implementing sustainable procurement in construction projects. The framework will consist of important factors driving the sustainable procurement system and their relationships to effectively produce the outputs of procurement processes that meets sustainable principles.
New Natural Coagulant Aid in Water Treatment
Authors: Chew Jenny Siew Lee , Ho Agnes Yin Yee , Lim Boon Chin , Chan Wai Loon , Ho Yeek Chia , Lim Jun Wei , Lai Soon Onn
Published: September 2018

Natural source of coagulant is certainly being considered in addressing the disadvantages associated with the use of inorganic coagulants. Annona muricata is hypothesized to be new material as natural coagulant aid in coagulation-flocculation process. On the other hand, due to the high lipids content in microalgae, namely, Chlorella vulgaris is used in producing renewable energy, i.e. biodiesel. Coagulation-flocculation is an effective method in microalgae harvesting. Thus, in this study, a novel natural coagulant aid extracted from fruit waste in algae harvesting. It is aimed to (1) to extract natural coagulant aid (hereafter is known as biopolymer) extracted from Annona muricata seeds in algae harvesting, and (2) to evaluate the operational conditions of coagulation-flocculation process by utilizing the biopolymer. As a result, it is observed that acid extraction and extraction through sodium chloride does not show any yield. On the other hand, the harvesting efficiency showed positive response as coagulant aid at 20 mg/L.
Biochemical Enhancement of Geotechnical Properties of Marginal Soils
Authors: Mohammed Murtala Hassan , Abdulfatah Ado Yusuf
Published: September 2018

Microbially-induced calcite precipitation (MICP) is a relatively new and sustainable soil improvement technique. This technique utilizes bio-activity of microorganism to precipitate calcite through metabolic activities of the organisms which decompose urea in to ammonium and carbon dioxide. The carbonate so produced combined with the supplied calcium to precipitate calcite. This calcite improves engineering properties of soil through the formation of coating and bonds between soil particles. Preliminary results have proved the feasibility of the isolated bacteria in MICP treatment technique to improve the engineering properties of marginal soil. The main objective of this study is to determine the preference conditions for effective MICP treatment in improving the soil engineering properties (Unconfined Compressive Strength, California Bearing Ratio and Hydraulic Conductivity) of a typical marginal soil. Variables such as; treatment duration (24, 48, and 72hours), reagent concentration (0.1, 0.25, 0.5, and 0.75M), and concentration of the isolates (1×105, 1×106, and 1×107cfu/ml) were considered in the MICP treatment. The results suggested that the preference treatment conditions were 72hours treatment duration, 0.75M reagent concentration, and 1×107cfu/ml concentration of the isolates. The corresponding alterations recorded were 94.86KN/m2 (295%) and 30.8% (92.5%) increment for CBR and UCS while 0.93X10-6m/s (78.95%) reduction was recorded for hydraulic conductivity. The calcite content showed a reasonably good comparison with the improvements in the soil engineering properties. The pH of effluents increased during MICP treatment indicating the presence of urease bio-activity.
An Attempt of Screw Driving Sounding Test in Malaysia
Authors: Marto Aminaton , Sakai Go , Suemasa Naoaki , Jamaludin Nadiah
Published: September 2018

Conventional soil investigation methods such as Mackintosh Probe Test (MPT) have limitations, e.g., require manual work for the equipment and data accuracy is low due to human error. While Standard Penetration test (SPT) needs high skilled workers and the cost per testing is expensive. Hence, Screw Driving Sounding test (SDS) was developed in Japan as a solution to the aforementioned disadvantages. An attempt was done to implement this test in Malaysia at different types of soils. This paper presents the results obtained from Batu Pahat and Cheras sites. Data from SDS tests were compared with the existing data of SPT and MPT available from Batu Pahat and Cheras sites, respectively. Results of the coefficient of determination, R2 = 0.721 for Batu Pahat Site and 0.851 for Cheras Site illustrate that the SPT and MPT results are highly correlated with SDS test results. From this preliminary findings, it shows that SDS test has the potential for soil characterizations in soil investigation work in Malaysia.
Properties of Crumb Rubber and Latex Modified Asphalt Binders using Superpave Tests
Authors: Sutanto Muslich , Bala Nura , Al Zaro Kemal , Sunarjono Sri
Published: September 2018

Polymer modified binders have been used for long time to improve the quality of asphalt pavement. This study investigates the effect of crumb rubber and latex on the properties of bitumen binders. Crumb rubber and latex were added to the control 60/70 pen grade bitumen. Four different proportions of crumb rubber and latex were considered in this study: 0%, 4%, 6% and 8% by weight of bitumen binder. The effect of crumb rubber and latex were evaluated through standard penetration and softening point tests as well as dynamic shear rheometer (DSR) test. Temperature ranges of 20°C - 40°C were used for the DSR rheological testing. The results showed that the addition of crumb rubber and latex leads to a promising improvement on the binder properties. A reduction in penetration and an increase in softening point temperature were observed with the addition of either crumb rubber or latex, this indicates improvement in stiffness and rutting resistance. The analysis on DSR results also show that the modified binders have good rutting resistance.
Use of Recycled Tyre Rubber in Non-structural Concrete
Authors: Waris Muhammad Bilal , Najwani Hussain , Al-Jabri Khalifa , Al-Saidy Abdullah
Published: September 2018

To manage tyre waste and conserve natural aggregate resource, this research investigates the use of waste tyre rubber as partial replacement of fine aggregates in non-structural concrete. The research used Taguchi method to study the influence of mix proportion, water-to-cement ratio and tyre rubber replacement percentage on concrete. Nine mixes were prepared with mix proportion of 1:2:4, 1:5:4 and 1:2.5:3; water-to-cement ratio of 0.25, 0.35 and 0.40 and rubber to fine aggregate replacement of 20%, 30% and 40%. Compressive strength and water absorption tests were carried out on 100 mm cubes. Compressive strength was directly proportional to the amount of coarse aggregate in the mix. Water-to-cement ratio increased the strength within the range used in the study. Strength was found to be more sensitive to the overall rubber content than the replacement ratio. Seven out of the nine mixes satisfied the minimum strength requirement for concrete blocks set by ASTM. Water absorption and density for all mixes satisfied the limits applicable for concrete blocks. The study indicates that mix proportions with fine to coarse aggregate ratio of less than 1.0 and w/c ratio around 0.40 can be used with tyre rubber replacements of up to 30 % to satisfy requirements for non-structural concrete.
Performance Evaluation of Ordinary Portland Cement with GGBFS and Portland Slag Cement at Same GGBFS Replacement Level in Concrete
Authors: Chokkalingam Ramesh Babu , Rajakannu Manikandan
Published: September 2018

Literature review indicates that the usage of mineral admixtures (Fly ash, Ground Granulated Blast Furnace Slag, Silica Fume and Rice Husk ash) significantly improves the durability of concrete structures. Though it is reported as best alternative materials for improving durability of concrete structures, it was not very well received in government projects in India till 1990. However, for the past two decades, the usage of mineral admixtures directly or in the form of blended cement in concrete have significantly increased. Major concern of using mineral admixtures which was persisting among majority of the Ordinary Portland Cement (OPC) users are (i) delayed setting and strength gain, affecting the rate of construction, (ii) inconsistent in quality of mineral admixtures, mostly happened in site blending (iii) no established results pertains to Indian condition. In India, mostly the usage of mineral admixtures in concrete are used as a replacement for OPC, specifically in Ready Mix Concrete and site batching plant. However, few literature have reported that usage of mineral admixtures in the form of blended cement which is made at cement manufacturing plant by either intergrinding or blending will exhibits better concrete properties due to consistent quality and better quality control practice followed. Hence, the authors have undertaken this study to investigate the performance of mineral admixtures (only GGBFS) as direct replacement materials and as blended cement in concrete. In order to understand in detail, both as replacement of OPC and in the form of PSC, was undertaken on various cement content in concrete, i.e., 300, 320, 340, 360, 380 kg/m3. Results of compressive strength at various age of curing indicates that usage of GGBFS in the form of Portland Slag Cement (PSC) shows better performance than as a replacement of OPC in concrete.
Effects of Incorporating Fiber Cocktail on Mechanical Properties of Concrete
Authors: Ahmad Saeed , Elahi Ayub , Iqbal Hafiz Waheed , Mehmood Faiza
Published: September 2018

The objective of this research work was to determine the effect of fiber cocktail on mechanical properties of concrete. Three types of fibers were used namely monofilament polypropylene fiber, steel fiber and glass fiber. Steel and glass fiber were incorporated in concrete at different dosages while the content of Polypropylene fiber was kept constant. For this purpose, cubes (150×150×150mm) and prisms (101×101×508mm) were casted for compressive strength test on cubes and Two-Point load test on prisms. Eighteen different mixes were prepared such as control mix, single fiber concrete, double hybrid concrete and triple hybrid concrete. It was observed that both compressive and flexural strength increased with addition of single, double and triple fibers. However, the strengths of triple hybrid concrete were observed to be lesser as compared to single and double hybrid concrete.
Tensile Properties of Epoxy Grout Incorporating Graphene Nanoplatelets for Pipeline Repair
Authors: Zainal Nurfarahin , Arifin Hanis Hazirah , Zardasti Libriati , Yahaya Nordin , Lim Kar Sing , Lai Jian Wey , Md Noor Norhazilan
Published: September 2018

In oil and gas industry, fibre-reinforced polymer (FRP) composite are widely used to repair pipeline subjected to external metal loss. This repair technique can be done by incorporating epoxy grout as infill material to smoothen the defect on pipeline surface and later wrapped with a composite wrap to restore the strength of the pipe. This paper attempts to investigate the behaviour of an epoxy grout with 0.5wt% graphene nanoplatelets (GnPs) under tensile loading according to the ASTM D638. GnPs were dispersed through the sonication method followed by calendering process to ensure an optimum enhancement in the properties of polymer matrix can be achieved. The results show positive improvement in terms of strength and Young's modulus of tested grout with the inclusion of GnPs. It shows that the presence of low concentration of GnPs as an additive has a significant reinforcement effect by improving tensile properties of epoxy grout up to 14% as compared to control sample.
Thermal Insulation of Residential Construction through the Study of Temperature Difference of Bricks
Authors: Raf'ee Sayang Syazanna , Liew Mohd Shahir , Zawawi Noor Amila , Danyaro Kamaluddeen Usman
Published: September 2018

This study seeks to measure the temperature difference of 3 types of interlocking bricks and 2 types of conventional bricks, all which are available in Malaysian market. The study aims to assist Malaysia’s residential construction dilemma in masonry. This is done by constructing 5 models using different types of bricks with the same dimensions, finishes and placed in the same area. Six points were taken to measure the temperature differences. The equipment used are 6 Thermocouples and HOBO UX120-014M data logger. Intervals of 15 minutes were recorded with duration of four months in Tronoh, Perak. Results show the best performed brick is IB2, even though IB1 and Clay bricks depict significant temperature differences. Comparing the temperature differences of IB1 and Clay brick, IB1 provide a better performance in a hot weather due to its higher thermal conductivity.
3D Numerical Simulation of Seamless Pipe Piercing Process by Fluid-Structure Interaction Method
Authors: Topa Ameen , Kim Do Kyun , Kim Youngtae
Published: September 2018

Seamless pipes are produced using piercing rolling process in which round bars are fed between two rolls and pierced by stationary plug. During this process, the material undergoes severe deformation which renders it impractical to perform the numerical simulations with conventional finite element methods. In this paper, three dimensional numerical simulations of the piercing process are performed with Fluid-Structure Interaction (FSI) Method using Arbitrary Lagrangian-Eulerian (ALE) Formulation with LS DYNA software. The results of numerical simulations agree with experimental data of Plasticine workpiece and the validity of the analysis method is confirmed.
Performance Evaluation of Geocomposite Reinforcement in Flexible Pavements using Marshall Test Protocol
Authors: Qadir Adnan , Choudhary Karam-un-Nisa
Published: September 2018

Asphalt concrete pavements are prone to cracking due to external loads and extreme weathering conditions. Generally the failed asphalt concrete is over laid with new asphalt concrete surface to improve the riding surface; however after sometime the crack reappears in the form of reflective cracking. Studies have found that such cracks can be controlled by introduction of Geo-synthetics layer before overlaying. The presented study presents one such effort in which the performance of such modification was evaluated by testing a number of modified specimens using Marshall’s test protocol. The resulting Stability flow quotient at optimum asphalt content showed no appreciable improvement as expected. Hence it can be concluded that the performance of Geocomposite modified asphalt concrete cannot be evaluated using Marshall Test protocols.
Application of Stochastic Flood Forecasting Model Using Regression Method for Kelantan Catchment
Authors: Osman Sazali , Aziz Norizan Abdul , Husaif Nurul , Sidek Lariyah Mohd , Shakirah Aminah , Hanum Faezah , Basri Hidayah
Published: September 2018

Flood is without doubt the most devastating natural disasters, striking numerous regions in Malaysia each year. During the last decades, the trend in flood damages has been growing exponentially. This is a consequence of the increasing frequency of heavy rain, changes in upstream land-use and a continuously increasing concentration of population and assets in flood prone areas. Malaysia, periodically, have faced with huge floods since previous years. Kelantan River basin, which located in the Northeast of Peninsular Malaysia, is prone to flood events in Malaysia. Kelantan River is the principal cause of flooding because it is constricted at its lower reaches. The capacity of the river at the downstream coastal area is less than 10,000 m3/s, therefore flood that exceeds this capacity will overspill the banks and discharge overland to the sea. Realizing the seriousness of the problems, it is vital in providing in time useful information for making crucial decisions especially to provide warning for any potential flood occurrence. In this study, stochastic flood forecasting model using stage regression method was applied to Kelantan River basin, in which the regression coefficients and equations was derived from the least square principle. The stochastic model were calibrated and validated which then shows that the equations derived are suitable to predict the hydrograph in Kelantan River basin. In conclusion, establishing a flood forecasting system would enhance the effectiveness of all other mitigation measures by providing time for appropriate actions. This has increased the importance of flood modelling for flood forecasts to issue advance warning in severe storm situations to reduce loss of lives and property damage.