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Wyświetlanie 1-14 z 14
Tytuł:
Homogeneity and heterogeneity of the workforce: leveraging on diversity management to build inclusive workplace
Jednorodność i niejednorodność siły roboczej: zarządzanie różnorodnością w celu stworzenia miejsca pracy umożliwiającego integrację społeczną
Autorzy:
Rahim, A. G.
Oluwafemi, A.
Afolabi, A. A.
Powiązania:
https://bibliotekanauki.pl/articles/325765.pdf
Data publikacji:
2017
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
diversity
inclusion
equal employment opportunity
gender
diversity management practices
human resource management
różnorodność
integracja społeczna
równe szanse zatrudnienia
płeć
praktyki zarządzania różnorodnością
zarządzanie zasobami ludzkimi
Opis:
Given the globalized nature of the contemporary business environment, organisations require more interaction among people from diverse cultures and heterogeneous demographic characteristics than ever before. Consequently, organisations have no other feasible choice but to adopt and implement diversity initiatives that align sameness or differences in workforce composition to build inclusive workplace. This paper sought to examine the homogeneity and heterogeneity of the workforce with a view of leveraging on diversity management to build inclusive workplace. The paper review extant studies on the subject matter to achieve the focal objectives highlighted. The paper documented that diversity management is characterized by ambiguity; as there are numerous diverse reasons and initiatives of diversity management. Moreover, effective diversity management propel cohesion that integrate all members of the organization. The paper further noted that organisational commitment to diversity is rooted less on a moral dictate toward justice and fairness and more on self-serving desire to address external pressures and achieve other desirable outcomes. Consequently, most firms approached diversity issue as a basic response to change which does not capture its essence. The paper concludes that diversity management is good for business and should be viewed as a key mechanism for improving business competitiveness. Similarly, effective diversity management can lead to better talent management and possession of competence to solve long-term problems.
Ze względu na globalny charakter współczesnego otoczenia biznesu, organizacje potrzebują więcej interakcji między osobami z różnych kultur, o niejednorodnych cechach demograficznych, w większym stopniu niż kiedykolwiek wcześniej. W konsekwencji organizacje nie mają innego wyboru, niż zarządzanie różnorodnością, która pozwoli na dostosowanie sposobu zarządzania do zmieniających się warunków i umożliwi poprawę integracji społecznej. Niniejszy artykuł podejmuje próbę badań w zakresie jednorodności i niejednorodności siły roboczej z myślą o wykorzystaniu tej koncepcji do budowy miejsca pracy, umożliwiającego integrację społeczną. Autorzy dokonują przeglądu istniejących publikacji na omawiany temat. Analiza pozwala na stwierdzenie, że zarządzanie różnorodnością charakteryzuje się wysoką wieloznacznością, ponieważ istnieje wiele różnorodnych przyczyn i inicjatyw zarządzania różnorodnością. Ponadto, skuteczne zarządzanie różnorodnością wymaga działań, które integrują wszystkich członków organizacji. Ponadto, w artykule zauważono, że zaangażowanie organizacyjne w zakresie zarządzania różnorodnością jest mniej zakorzenione w postawach moralnych wobec sprawiedliwości i uczciwości, a bardziej oparte na egoistycznych chęciach zaspokojenia nacisków zewnętrznych i osiągnięcia innych pożądanych rezultatów przez organizacje. W konsekwencji większość firm traktuje kwestię różnorodności jako podstawową odpowiedź na zmiany, które zachodzą w obszarze zasobów siły roboczej. W artykule stwierdza się, że zarządzanie różnorodnością jest dobre dla biznesu i powinno być postrzegane jako kluczowy mechanizm dla poprawy konkurencyjności przedsiębiorstw. Podobnie, skuteczne zarządzanie różnorodnością może prowadzić do lepszego zarządzania talentami i posiadania przez organizację kompetencji do rozwiązywania problemów długoterminowych.
Źródło:
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska; 2017, 100; 409-426
1641-3466
Pojawia się w:
Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural and Optical Characterizations of~Ge Nanostructures Fabricated by~RF Magnetron Sputtering and Rapid Thermal Processing
Autorzy:
Abd Rahim, A.
Hashim, M.
Rusop, M.
Jumidali, M.
Powiązania:
https://bibliotekanauki.pl/articles/1490688.pdf
Data publikacji:
2012-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.55.ag
68.60.Dv
61.46.Hk
78.67.Bf
61.05.C-
Opis:
In this work, we use a simple and cost effective technique of sputtering followed by the rapid thermal processing at 900C for 30 s to form Ge nanostructures on the Si(100) substrate. A layer of Ge (300 nm) and Si cap layer (100 nm) were deposited using RF magnetron sputtering. Two samples were prepared: Ge layer with Si capping (Si/Ge/Si) and Ge layer without Si capping (Ge/Si). Scanning electron microscopy shows that subsequent annealing in a rapid thermal processing gives uniformed Ge or SiGe islands with an estimated size of 100-500 nm. For the Ge/Si sample, under post growth annealing there had vanished the deposited Ge layer as confirmed by energy dispersive X-ray analysis. Atomic force microscopy shows that the surface roughness increases by a factor of 15.55% as the islands formed. The Raman spectrum shows that good crystalline structures of the Ge and SiGe peaks are produced. High resolution X-ray diffraction reveals cubic and tetragonal Ge phases with estimated average crystallite sizes of 42 nm and 20 nm, respectively. The results showed that it is possible to grow high quality Ge and SiGe nanostructures using a simple technique of sputtering for potential applications in photonics and high speed devices.
Źródło:
Acta Physica Polonica A; 2012, 121, 1; 16-19
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Formation of Uniform Germanium Islands on Silicon Substrate Using Nickel as Catalyst by Thermal Evaporation Method
Autorzy:
Jumidali, M.
Hashim, M.
Abdul Aziz, A.
Abd Rahim, A.
Powiązania:
https://bibliotekanauki.pl/articles/1193093.pdf
Data publikacji:
2015-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Ea
81.10.Bk
81.15.-z
Opis:
Uniform germanium islands (GIs) were grown on Si (100) using a nickel layer as catalyst through the physical vapor deposition of germanium (Ge) powder at 1000°C at different deposition times. Prior to the deposition of Ge layer, nickel (Ni) catalyst was deposited on silicon substrates via radio frequency magnetron sputtering technique. Scanning electron microscopy results showed that the increase in deposition time resulted in a variation in surface morphology. Energy dispersive X-ray spectrometer analysis found that the GI samples composed of Ni element indicating the role of Ni in uniform Ge islands formation. The X-ray diffraction pattern spectra revealed that the GIs exhibited a Ge cubic structure and the intensity of Ge peaks varies with deposition time. In-plane strain indicated that the strain caused by the substrate is tensile and changed to compressive strain at the longer deposition time. The Raman spectra exhibited a red shift in the Ge-Ge peak, compared with the bulk Ge, as a result of compressive strain of the GIs. Fourier transform infrared spectrum analysis also indicated that the optical band gap Eg values of GIs can be varied by deposition time.
Źródło:
Acta Physica Polonica A; 2015, 127, 4; 1068-1071
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Streamlining Malaysias National R&D Areas
Priorytetyzacja kluczowych obszarów badawczych w Malezji
Autorzy:
Rahim, R. A.
Emran, N. M.
Powiązania:
https://bibliotekanauki.pl/articles/256116.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Eksploatacji - Państwowy Instytut Badawczy
Tematy:
priorytetowe obszary badawcze
Krajowa Rada ds. Nauki i Badań
Malezja
NSRC
metodyka foresightu
foresight
myForesightŽ-Malezyjski Krajowy Instytut ds. Foresightu
prioritised R&D areas
Malaysia's National Science & Research Council
foresight methodology
Malaysia
myForesightŽ Malaysia's National Foresight Institute
Opis:
This article provides a brief on the processes and methodologies undertaken in conducting the R&D areas prioritisation in Malaysia. The listed prioritised areas will provide the basis for resource allocation of the country for the next 10 years and beyond. The R&D prioritisation initiative involved intense iterative periods of open reflection, networking, consultation and discussion, leading to the joint refining of future visions, long term goals and the common ownership of the focus areas. There are also dedicated groups that are responsible in monitoring output of each discussion to ensure the coordination, cohesiveness and inclusiveness of the necessaries. Endorsement of the recommendation will be the foundation and guidelines for further work especially in steering future R&D activities in Malaysia.
Artykuł prezentuje procesy i metodykę priorytetyzacji obszarów badawczych kluczowych dla rozwoju Malezji, które w najbliższym dziesięcioleciu otrzymają największe dofinansowanie. Priorytetyzacja obszarów badawczych przeprowadzona została na drodze iteratywnych konsultacji, dyskusji i networkingu, których rezultatem było opracowanie przyszłościowych wizji i długoterminowych celów wspólnych dla całego malezyjskiego społeczeństwa. Proces priorytetyzacji obszarów badawczych był monitorowany i koordynowany przez specjalnie powołane grupy ekspertów, których celem było zapewnienie spójności i integracji potrzeb społecznych. Zatwierdzenie rekomendacji stanowić będzie podstawę i wytyczne do dalszych prac w obszarze ukierunkowywania przyszłych działań badawczo-rozwojowych w Malezji.
Źródło:
Problemy Eksploatacji; 2012, 4; 139-150
1232-9312
Pojawia się w:
Problemy Eksploatacji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inducing salt tolerance in french marigold (Tagetes patula) through seed priming
Autorzy:
Afzal, I.
Rahim, A.
Qasim, M.
Younis, A.
Nawaz, A.
Bakhtavar, M.A.
Powiązania:
https://bibliotekanauki.pl/articles/11825212.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
Opis:
The present study investigates the potential of seed priming for induction of salt tolerance in French marigold at early growth stage. Treatments were combination of priming techniques viz. hydropriming, halopriming (50 mM CaCl2), hormonal priming with salicylic acid (100 ppm) and ascorbate priming (100 ppm) each for 24 h. Primed seeds were exposed to salinity levels (0; 50 and 100 mM NaCl) during germination and emergence assays. All priming treatments hastened germination and emergence attributes under saline or non-saline conditions as compared to those of non-primed (control) seeds. Seeds of French marigold primed with ascorbate followed by CaCl2, salicylic acid and hydropriming enhanced final germination, speed of germination, root and shoot length and dry mass of French marigold seedlings. This was interpreted by minimized mean emergence time and time to 50% emergence. Additionally, it was also observed that all priming agents particularly calcium salt and ascorbate maintained ionic homeostasis in salt stressed seedlings. It is concluded that CaCl2, ascorbate and salicylic acid were the most effective priming agents to ameliorate the adverse effects of salinity in French marigold due to lower uptake of Na+ and higher uptake of K+ in the seedlings.
Źródło:
Acta Scientiarum Polonorum. Hortorum Cultus; 2017, 16, 3; 109-118
1644-0692
Pojawia się w:
Acta Scientiarum Polonorum. Hortorum Cultus
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of organophilization and interlamellar silylation of montmorillonite on compatiblization of polymer composites
Autorzy:
Rahim, M. A.
Ismail, M.
Kandi, A.
Powiązania:
https://bibliotekanauki.pl/articles/102045.pdf
Data publikacji:
2016
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
nanocomposites
montmorillonite
organophilization
polymer composites
compatibilization
Opis:
Sodium montmorillonite (Na-Mt) was modified by cetyltriemethylammoniumbromide (CTAB) through cation exchange technique followed by grafting with 3-aminopropyltriethoxysilane (APT). The effects of organophillic surface treatments of montmorillonite on compatibilization of natural rubber (NR) /acrylonitrile butadiene rubber (NBR) blends was investigated. Physico-mechanical properties of rubber nanocomposites compatibilized with organomodified montmorillonite revealed strong nanocomposite with high tensile properties, impact strength and good resistance to flex fatigue, abrasion and compression set. Dynamic mechanical thermal analysis (DMTA) revealed a marked increase in storage modulus (E’) and lesser damping characteristics of organically modified clay mineral polymer nanocomposites (CPN) due to intercalation of organophilic montmorillonite by rubber matrix. The morphology of the blends became homogeneous and smoother with the presence of exofoliated/intercalated organically modified montmorillonite. Organomodified layered silicate sheets of montmorillonite greatly enhanced barrier properties by creating tortuous path that retarded the progress of solvent molecules through rubber matrix.
Źródło:
Advances in Science and Technology. Research Journal; 2016, 10, 32; 206-2016
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hybrid cryptography with a one-time stamp to secure contact tracing for COVID-19 infection
Autorzy:
El-Douh, Ahmed Abdel-Rahim
Lu, Song Feng
Elkouny, Abdelatif A.
Amein, A.S.
Powiązania:
https://bibliotekanauki.pl/articles/2055157.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
hybrid cryptography
digital signature
RSA
AES
asymmetric cryptography
symmetric cryptography
cybersecurity
COVID-19
kryptografia hybrydowa
podpis elektroniczny
kryptografia asymetryczna
kryptografia symetryczna
cyberbezpieczeństwo
Opis:
The COVID-19 pandemic changed the lives of millions of citizens worldwide in the manner they live and work to the so-called new norm in social standards. In addition to the extraordinary effects on society, the pandemic created a range of unique circumstances associated with cybercrime that also affected society and business. The anxiety due to the pandemic increased the probability of successful cyberattacks and as well as number and range. For public health officials and communities, location tracking is an essential component in the their efforts to combat the disease. The governments provide a lot of mobile apps to help health officials to trace the infected persons and contact them to aid and follow up on the health status, which requires an exchange of data in different forms. This paper presents the one-time stamp model as a new cryptography technique to secure different contact forms and protect the privacy of the infected person. The one-time stamp hybrid model consists of a combination of symmetric, asymmetric, and hashing cryptography in an entirely new way that is different from conventional and similar existing algorithms. Several experiments have been carried out to analyze and examine the proposed technique. Also, a comparison study has been made between our proposed technique and other state-of-the-art alternatives. Results show that the proposed one-time stamp model provides a high level of security for the encryption of sensitive data relative to other similar techniques with no extra computational cost besides faster processing time.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2022, 32, 1; 139--146
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of High Entropy Alloy as Catalyst for Azo Dye Degradation in Fenton Process
Autorzy:
Hassan, Nur Hudawiyah Abu
Nasir, Nisa Syukrina Mat
Rahman, S. N. A.
Irfan, Abd Rahim
Nordin, Norhuda Hidayah
Powiązania:
https://bibliotekanauki.pl/articles/2203739.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
azo dye
catalyst
fenton process
high entropy alloys
HEAs
Opis:
Azo dye is widely used in the textile industry since it is cost effective and simple to use. However, it becomes a continuous source of environmental pollution due to its carcinogenicity and toxicity. Various methods had been used to remove the azo dye in solution. One of the famous and frequently used is the Fenton process. The Fenton process is one of the advanced oxidation processes where iron catalysed hydrogen peroxide to generate hydroxyl radical. Treating azo dyes in solution requires a catalyst to enhance the process of degradation. Herein, high entropy alloys (HEAs) have been proposed as a catalytic material to enhance the performance of Fenton process for azo dye degradation. HEAs have been reported as a promising catalyst due to its high surface area. The higher the number of active sites, the higher the rate of azo dye degradation as more active sites are available for adsorption of azo dyes. The results have shown that HEAs can be used as a catalyst to fasten the Fenton reaction since the degradation time is proven to be shorter in the presence of HEAs. The method derived from the result of this study will contribute in treating azo dyes for wastewater management in the Fenton process.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 209--213
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Utilization of services and referrals through dental outreach programs in rural areas of India. A two year study
Autorzy:
Asawa, K.
Bhanushali, N.V.
Tak, M.
Kumar, D.R.V.
Rahim, M.F.B.A.
Alshahran, O.A.
Divakar, D.D.
Powiązania:
https://bibliotekanauki.pl/articles/877920.pdf
Data publikacji:
2015
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Tematy:
motivation
utilization
service
referral
dental outreach programme
rural area
rural population
India
Opis:
Background. Oral health care services are often sparse and inconsistent in India therefore it is often difficult for poor people to get access to the oral health care services. The approach by dental institutions with the help of community outreach programs is a step ahead in overcoming this situation. Objectives. The study was conducted to evaluate the number of patients, disease pattern and the services provided in the outreach programmes and also effectiveness of patient referral. Methods. A retrospective study was conducted and the data were obtained from records of outreach programs conducted, in last 2 years by Pacific Dental College and Hospital. The data were analysed using descriptive statistics for the computation of percentages Chi-square test was applied to know the association of effectiveness of referral with age and gender. Confidence level and level of significance was fixed at 95% and 5% respectively. Results. A total of 22982 individuals in the age group of 4-80 years attended the outreach program. Dental caries (42.3%), periodontal diseases (63.2-69.0%) and dental fluorosis (33.7-35.0%) were commonly observed diseases. Effectiveness of referral was significantly high among the middle age adults and females (P<0.05). The effectiveness of referral was highly improved in 2013 after establishment of certain guidelines and strategies. Conclusion. The approaches by dental institutions with the help of community outreach programs can spread awareness and disseminate treatment and thereby enhancing access to care and eliminating access to care within the rural communities.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2015, 66, 3
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental investigation of chopped steel wool fiber at various ratio reinforced cementitious composite panels
Autorzy:
Rmdan Amer, Akrm A.
Al Bakri Abdullah, Mohd Mustafa
Ming, Liew Yun
Aziz, Ikmal Hakem A.
Mohd Tahir, Muhammad Faheem
Abd Rahim, Shayfull Zamree
Amer, Hetham A. R.
Powiązania:
https://bibliotekanauki.pl/articles/1852332.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
włókno stalowe
włókno posiekane
wełna stalowa
kompozyt cementowy
płyta kompozytowa
nośność
steel fiber
chopped fiber
steel wool
cementitious composite
composite panel
load carrying capacity
Opis:
The flexural toughness of chopped steel wool fiber reinforced cementitious composite panels was investigated. Reinforced cementitious composite panels were produced by mixing of chopped steel wool fiber with a ratio range between 0.5% to 6.0% and 0.5% as a step increment of the total mixture weight, where the cement to sand ratio was 1:1.5 with water to cement ratio of 0.45. The generated reinforced cementitious panels were tested at 28 days in terms of load-carrying capacity, deflection capacities, post-yielding effects, and flexural toughness. The inclusion of chopped steel wool fiber until 4.5% resulted in gradually increasing load-carrying capacity and deflection capacities while, provides various ductility, which would simultaneously the varying of deflection capability in the post-yielding stage. Meanwhile, additional fiber beyond 4.5% resulted in decreased maximum load-carrying capacity and increase stiffness at the expense of ductility. Lastly, the inclusion of curves gradually.
Źródło:
Archives of Civil Engineering; 2021, 67, 3; 661-671
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extraction of Tannic Acid from Kenaf Bast Fibre using Ultrasonic Assisted Extraction
Autorzy:
Mohamad, Mardawani
Ibrahim, H. A.
Nasir, M. F. M.
Mohidem, Nur Atikah
Shoparwe, N. F.
Teo, Pao Ter
Masri, Mohamad Najmi
Irfan, Abd Rahim
Powiązania:
https://bibliotekanauki.pl/articles/2134102.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ultrasonic assisted extraction
UAE
sonication time
duty cycle
extraction process
kenaf bast fibre
Opis:
Tannic acid or tannin, type of phenolic compound contains in kenaf bast fibre. Conventional extraction has certain limitations in terms of time, energy, and solvent consumption. Ultrasound assisted extraction (UAE) can extract bioactive components in shorter time, low temperature, with lesser energy and solvent requirement. UAE as alternative extraction technique is better equipped to retain the functionality of the bioactive compounds. In this study, the conditions for ultrasound assisted extraction (UAE) of tannic acid from kenaf bast fibre by assessing the effect of sonication time and different duty cycles were optimized. The use of ultrasound to extract tannic acid from kenaf bast fiber was evaluated. Ultrasound-assisted extraction (UAE) was carried out using ethanol as solvent to intensify the extraction efficacy. Phytochemical screening was conducted to identify the presence of tannic acid in extracts. The extracts then were analyzed using High-Performance Liquid Chromatography (HPLC) and Scanning Electron Microscopy (SEM). It was found that 0.2429 mg/mL of tannic acid was obtained under the extraction conditions of extraction temperature of 40℃, sonication time of 20 minutes and duty cycle of 50%. From SEM analysis, it was found that the raw sample demonstrated rough surface and no porous but kenaf bast fibre display smoother surface with less impurities and few pores appeared after the extraction process using UAE. These results indicate that ultrasound-assisted extraction is an efficient method for extracting tannic acid from kenaf bast fibre with the advantages of lower extraction time and higher extraction yield.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 3; 1061--1066
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Silica Bonding Reaction on Fly Ash Based Geopolymer Repair Material System with Incorporation of Various Concrete Substrates
Autorzy:
Al Bakri Abdullah, Mohd Mustafa
Aziz, Ikmal Hakem A.
Zailani, Warid Wazien Ahmad
Rahim, Shayfull Zamree Abd
Yong, Heah Cheng
Sandu, Andrei Victor
Peng, Loke Siu
Powiązania:
https://bibliotekanauki.pl/articles/2174557.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
fly ash geopolymer
repair material
concrete substrate
interfacial zone transition
Opis:
This paper presents an experimental investigation on the mechanical properties and microstructure of geopolymer repair materials mixed using fly ash (FA) and concrete substrates. An optimal combination of FA and concrete substrate was determined using the compressive test of geopolymer mortar mixed with various concrete substrate classes. It was found that the contribution of (C35/45) concrete substrates with the FA geopolymer mortar increases the 28-day bonding strength by 25.74 MPa. The microstructure analysis of the samples using scanning electron microscopy showed the denser structure owing to the availability of high calcium and iron elements distribution. These metal cations (Ca2+ and Fe3+) are available at OPC concrete substrate as a result from the hydration process reacted with alumina-silica sources of FA and formed calcium aluminate silicate hydrate (C-A-S-H) gels and Fe-bonding linkages.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 4; 1277--1281
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal Insulation and Mechanical Properties in the Presence of Glas Bubble in Fly Ash Geopolymer Paste
Autorzy:
Shahedan, Noor Fifinatasha
Abdullah, Mohd Mustafa Al Bakri
Mahmed, Norsuria
Liew, Yun Ming
Shayfull, Zamree Abd Rahim
Aziz, Ikmal Hakem A.
Kadir, Aeslina Abdul
Sandu, Andrei Victor
Ghazali, Mohd Fathullah
Powiązania:
https://bibliotekanauki.pl/articles/2048833.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
glass bubble
thermal insulation
geopolymers
fly ash
Opis:
The density, compressive strength, and thermal insulation properties of fly ash geopolymer paste are reported. Novel insulation material of glass bubble was used as a replacement of fly ash binder to significantly enhance the mechanical and thermal properties compared to the geopolymer paste. The results showed that the density and compressive strength of 50% glass bubble was 1.45 g/cm3 and 42.5 MPa, respectively, meeting the standard requirement for structural concrete. Meanwhile, the compatibility of 50% glass bubbles tested showed that the thermal conductivity (0.898 W/mK), specific heat (2.141 MJ/m3 K), and thermal diffusivity (0.572 mm2 /s) in meeting the same requirement. The improvement of thermal insulation properties revealed the potential use of glass bubbles as an insulation material in construction material.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 1; 221-226
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Crumb rubber geopolymer mortar at elevated temperature exposure
Autorzy:
Azmi, Ahmad Azrem
Abdullah, Mohd Mustafa Al Bakri
Ghazali, Che Mohd Ruzaidi
Ahmad, Romisuhani
Jaya, Ramadhansyah Putra
Rahim, Shayfull Zamree Abd
Almadani, Mohammad A.
Wysłocki, Jerzy J.
Śliwa, Agata
Sandu, Andrei Victor
Powiązania:
https://bibliotekanauki.pl/articles/2173997.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
popiół lotny
zaprawa geopolimerowa
okruchy gumy
temperatura podwyższona
narażenie
fly ash
geopolymer mortar
crumb rubber
elevated temperature
exposure
Opis:
Low calcium fly ash is used as the main material in the mixture and the crumb rubber was used in replacing fine aggregates in geopolymer mortar. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) which were high alkaline solution were incorporated as the alkaline solution. The fly ash reacted with the alkaline solution forming alumino-silicate gel that binds the aggregate to produce a geopolymer mortar. The loading of crumb rubber in the fly ash based geopolymer mortar was set at 0% (CRGM-0), 5% (CRGM-5), 10% (CRGM-10), 15% (CRGM-15), and 20% (CRGM-20), respectively. NaOH solution (12M) and Na2SiO3 solution ratio is set constant at 2.5 for all geopolymer mixture and the fly ash to alkali activator ratio was kept at 2.0. The CRGM at 28 days of curing time was exposed to elevated temperature at 200ºC, 400ºC, 600ºC and 800ºC. The weight loss of the CRGM increases with increasing temperature at all elevated temperatures. However, the density and compressive strength of CRGM decrease with an increase of crumb rubber loading for all elevated temperature exposure. The compressive strength of CRGM reduced due to the fact that rubber decomposes between 200ºC and 600ºC thereby creating voids. CRGM-15 and CRGM-20 showed cracks developed with rough surface at 800ºC. Image obtained from scanning electron microscope (SEM) showed that, the CRGM changed significantly due to the decomposition of crumb rubber and evaporation of the free water at 400ºC, 600ºC and 800ºC.
Źródło:
Archives of Civil Engineering; 2022, 68, 3; 87--105
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
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