Metakaolin is a manufactured pozzolan produced by thermal processing of purified kaolinitic clay using electrical furnace. This study has examined the effect of Metakaolin on the properties of cement and concrete at a replacement level of 0%, 5%, 10% and 15%. The parameters studied were divided into two groups which are chemical compositions, water requirement, setting time and soundness test were carried out for cementitous properties. Workability, compressive strength and bending strength were test for concrete properties. Hardened concrete was cured under different type of curing conditions and tested.. The result showed that the inclusions of Metakaolin as cement replacement minerals have change some of the cementitous and concrete properties. This research reveals, the optimum effect for cementitous and concrete properties for metakaolin was 10%.
Kehilangan jisim tulang adalah lebih ketara selepas menopaus. Jangka masa menopaus dan umur yang meningkat dikaitkan dengan penurunan jisim tubuh tanpa lemak, peningkatan lemak badan dan peningkatan berat badan. Kajian ini melihat sumbangan relatif jisim tubuh tanpa lemak dan lemak badan ke atas ketumpatan mineral tulang (KMT) di kalangan 139 wanita Cina posmenopaus sihat di Kuala Lumpur. KMT di kawasan seluruh tubuh, tulang belakang ( L2-L4), leher femur dan keseluruhan tulang pinggul diukur dengan alat dual-energy X-ray absorptiometry (DxA). Hasil kajian mendapati 80% daripada wanita posmenopaus Cina mempunyai jisim tulang yang rendah (osteopenia) manakala 8% daripada mereka mengalami osteoporosis di bahagian tulang belakang atau tulang pinggul. Secara keseluruhan, lemak badan mempunyai korelasi yang positif dengan KMT di semua bahagian diukur (keseluruhan tubuh, r = 0.265, p < 0.001; tulang belakang r = 0.214, p < 0.05, leher femur, r = 0.254, p < 0.001; keseluruhan tulang pinggul r = 0.332, p < 0.001). Jisim tubuh tanpa lemak juga mempunyai korelasi yang positif dengan KMT kebanyakan kawasan diukur (keseluruhan tubuh, r = 0.239, p < 0.001; leher femur r = 0.365, p < 0.001; keseluruhan tulang pinggul r = 0.352, p < 0.001) kecuali tulang belakang. Analisis regresi menunjukkan lemak badan dapat meramal KMT pada keseluruhan badan (p < 0.0001) dan tulang belakang (p < 0.005) manakala jisim tubuh tanpa lemak dapat meramal KMT pada tulang femur dan tulang pinggul (p < 0.0001). Hasil kajian menunjukkan kedua-dua lemak tubuh dan jisim tubuh tanpa lemak memainkan peranan dalam mempengaruhi KMT, di mana lemak badan memainkan peranan yang lebih di kalangan wanita posmenopaus. Oleh itu, wanita posmenopaus perlu elakkan mempunyai berat badan yang terlalu rendah (kurang lemak badan) dan mengekalkan jisim tubuh tanpa lemak untuk mencegah osteoporosis.
In ancient times, before Hippocrates, disease and illness were attributed as a sign of divine dismay, and the Gods needed to be appeased to achieve a cure. Hippocrates and his followers showed courage in breaking away from this paradigm. They moved away from the divine and supernatural, to focus on the biology of the body. In the process they put the patient at the centre of their focus. They collected detailed case histories, dismissed religious and supernatural explanations and developed remedies in the form of diets, exercise and mixed minerals and herbs based on their understanding of ill health.
XRF analysis was done on a local zircon samples and the result shows it has a high Fe, Th and U content. The high Fe content in Malaysian zircon had made the mineral to be classified as of a low-grade zircon. Presence of Fe in this mineral may be resulted from clay mineral coating found on the zircon surface. Chemical leaching technique was used for the removal of this Fe and the study also shows that a 600 o C heat pretreatment stage is important for the effectiveness of this process. Other parameters studied are the HCl concentration, leaching temperature and time. By using the optimum leaching parameters, the Fe content had been reduced to 0.049% and thus qualified it to be categorised as a premium grade zircon.
Daging memainkan peranan penting dalam diet seseorang. Daging kaya dengan sumber protein, vitamin B12, vitamin D, asid lemak Omega 3 dan mineral seperti zink dan ferum. Walaupun daging membekalkan pelbagai keperluan nutrien yang diperlukan oleh tubuh, tetapi pengambilan daging juga boleh membawa kesan negatif kepada kesihatan. Oleh itu, di dalam artikel ini perbincangan akan menyentuh kepada risiko pengambilan daging merah kepada kesihatan. Pengambilan daging merah dalam kekerapan dan kuantiti yang tinggi boleh menyebabkan pelbagai penyakit antaranya seperti kanser dan kardiovaskular. Perbincangan juga di lakukan terhadap risiko pengambilan daging putih terhadap kesihatan. Pengambilan daging putih boleh mengundang pelbagai kesan negatif kepada kesihatan disebabkan oleh penggunaan hormon, antibiotik dan vaksin. Sebagai alternatif, daging ayam organik merupakan daging yang dicadangkan diambil oleh pengguna di dalam diet seharian. Prinsip penternakan ayam organik yang mementingkan sumber makanan ternakan tanpa penggunaan baja kimia dan racun perosak, aspek perumahan dan persekitaran yang mengutamakan kebajikan ternakan serta penjagaan kesihatan ternakan tanpa menggunakan hormon, antibiotik dan vaksin turut dibincangkan.
The Bukit Lagong area is the most important aggregate supply centre in Selangor. Geological studies were carried out in four quarries in the Bukit Lagong area and samples were subjected to petrographic examination and accelerated expansion tests to assess the potential alkali-aggregate reactivity of granite aggregates. The granitic rocks comprise mainly of coarse grained megacrystic granite, minor medium grained megacrystic granite and microgranite. Petrographic examination showed that the primary minerals in these undeformed granitic rocks are not alkali reactive. Faulting and related alteration and mineralization have produced potentially alkali reactive minerals including microcrystalline and strained quartz and fine phyllosilicates. Marginally deleterious and deleterious expansion is shown by the accelerated mortar bar tests. Although alkali reactive rocks are present in some quarries in Bukit Lagong, their volume is small. When blended with the undeformed granitic rocks, the aggregates produced are not expected to cause alkali-aggregate reaction in concrete.
Hydraulic fracturing becomes more difficult when confronted with a formation of high fracturing pressure. In such formations, acidizing before the main fracturing treatment provide a method to reduce fracture pressure. The aim of this paper was to investigate the evolution of fracture pressure in a wellbore with acidizing. Five experiments were conducted to study the mechanisms of acid damage on reservoir minerals and cementing materials properties. Consequently, a mathematical model to predict fracture pressure with acidizing has been established and verified by field data. The analysis results showed that it is possible to reduce fracture pressure with decreased rock strength and fracture critical stress intensity factor by means of acid damage. Acid damage destroys the crystal structure of mineral particles, breaks the crystalline layers in cementing materials, increases rock porosity and reduces the rock strength. In addition, as the acid concentration, formation temperature and acid treatment time increased, it was useful to reduce fracture pressure in the wellbore. Using the proposed model, we were able to select the optimal acid damage construction parameters to reduce fracture pressure.
It is well-known that the characteristics of hardness and drillability are influenced by microstructure of rock. In this study, rock properties were analyzed on grain size and grain content. Coarse-grain and fine-grain sandstones were tested under successive indentation condition. Eighteen groups of sandstone and shale were employed for the drillability test. Indentation tests results showed that grain size influenced the low point of residual hardness, the crushing depth and volume and grain content influenced the peak point of hardness. The drillability values of shale increased with increasing contents of clay and quartz. Meanwhile, drillability values of sandstone increased with increasing content of quartz, but decreased with increasing content of clay. Therefore, these preliminary studies show great potential applications for selecting suitable bit type and formulating drilling program as a function of rock microstructure and crushing rock method for bit in the oil drilling.
The biophysical data presented in this article were collected in the east coast of Peninsular Malaysia from May to November 2009. These monthly surface data were obtained from 32 stations along the coastal-offshore transect and were analyzed to understand the spatial and temporal distributions of biophysical parameters during different monsoon seasons. The data presented here include sea surface temperature (SST), sea surface salinity (SSS), Secchi disk depth (SDD), Chlorophyll-a (Chl-a), suspended particulate matter (SPM), mineral suspended solid (MSS) and chromophoric dissolved organic matter (CDOM).
This study was carried out on the hilly topographic area in Kundasang, Sabah. This area is known to be extremely prone to landslides that occurred either naturally or by human interference to natural slopes. Aerial photographs interpretation was conducted in order to identify landslide distributions across three assessment years (2012, 2009 and 1984). These datasets were classified into two landslides groups based on their occurrences; natural and artificial. A total of 362 naturally occurring landslides were identified and another 133 are artificial slope landslides. Physical parameters which include lithology, slope angle, slope aspect and soil series were analyzed with each landslide group to examine the different influence of these parameters on each of the group. From the analysis, the landslide density for the natural landslide group shows that more than 35° slope angle and slope aspect facing east and southwest are prone to landslides. In terms of geological materials, high landslide density is recorded in the phyllite, shale, siltstone and sandstone lithologies group and the Pinosuk, Kepayan and Trusmadi soil series. In contrast, for the artificial
slope landslide, high landslide density is observed in the 25°-35° slope angle and similar density in every slope aspect classes. The geological materials however have similar landslide density across their factors’ classes. The landslide density technique was also used to generate the landslide susceptibility maps for both landslide conditions. Validation of the maps shows acceptable accuracy of 71% and 74%, respectively, for both natural and artificial slope landslide susceptibility maps and this shows that these maps can be used for future land use planning.
Ethylenediaminetetraacetic acid (EDTA) can serve as a washing agent in the remediation of low-permeability layers contaminated by heavy metals (HMs). Therefore, batch adsorption experiments, where pure quartz (SM1) and mineral mixtures (SM2) were used as typical soil minerals (SMs) in low-permeability layers, were implemented to explore the effects of different EDTA concentrations, pH, and exogenous chemicals on the HM-SM-EDTA adsorption system. As the EDTA concentration increased, it gradually cut down the maximum Cd adsorption capacities of SM1 and SM2 from approximately 135 to 55 mg/kg and 2660 to 1453 mg/kg; and the maximum Pb adsorption capacities of SM1 and SM2 were reduced from 660 to 306 mg/kg and 19,677 to 19,262 mg/kg, respectively. When the initial mole ratio (MR = moles of HM ions/sum of moles of HM ions and EDTA) was closer to 0.5, the effect of EDTA was more effective. Additionally, EDTA worked well at pH below 7.0 and 4.0 for Cd and Pb, respectively. Low-molecular-weight organic acids (LMWOAs) affected the system mainly by bridging, complexation, adsorption site competition, and reductive dissolution. Cu2+, Fe2+ ions could significantly increase the Cd and Pb adsorption onto SM2. Notably, there were characteristic changes in mineral particles, including attachment of EDTA and microparticles, agglomeration, connection, and smoother surfaces, making the specific surface area (SSA) decrease from 16.73 to 12.59 m2/g. All findings indicated that EDTA could effectively and economically reduce the HM adsorption capacity of SMs at the reasonable MR value, contact time, and pH; EDTA reduced the HM adsorption capacity of SMs not only by complexation with HM ions but also by decreasing SSA and blocking active sites. Hence, the acquired insight from the presented study can help to promote the remediation of contaminated low-permeability layers in groundwater.
In recent years, off-site volumetric construction has been promoted as a viable strategy for improving the sustainability of the construction industry. Most prefabricated prefinished volumetric construction (PPVC) structures are composed of either steel or concrete; thus, it is imperative to carry out life cycle assessments (LCAs) for both types of structures. PPVC is a method by which free-standing volumetric modules-complete with finishes for walls, floors, and ceilings-are prefabricated and then transferred and erected on-site. Although many studies have examined these structures, few have combined economic and environmental life cycle analyses, particularly for prefinished volumetric construction buildings. The purpose of this study is to utilize LCA and life cycle cost (LCC) methods to compare the environmental impacts and costs of steel and concrete PPVCs "from cradle to grave." The results show that steel necessitates higher electricity usage than concrete in all environmental categories, while concrete has a higher emission rate. Steel outperforms concrete by approximately 37% in non-renewable energy measures, 38% in respiratory inorganics, 43% in land occupation, and 40% in mineral extraction. Concrete, on the other hand, performs 54% better on average in terms of measures adopted for greenhouse gas (GHG) emissions. Steel incurs a higher cost in the construction stage but is ultimately the more economical choice, costing 4% less than concrete PPVC owing to the recovery, recycling, and reuse of materials. In general, steel PPVC exhibits better performance, both in terms of cost and environmental factors (excluding GHG emissions). This study endeavors to improve the implementation and general understanding of PPVC.
Separation materials have received increasing attention given their broad applications in the management of environmental pollution. It is desired to balance the contradiction between high separation efficiency and selectivity of separation materials. The integration of ball-milled bone chars with electrospun membranes might achieve this balance. In this study, electrospun cellulose/chitosan/ball-milled bone char (CL/CS/MB) membranes were by well-dispersing ball-milled bone chars with nanoscale size (98.9-167.5 nm) and developed porosity (40.2-373.1 m2/g) in the electrospinning solvent. The synergistic integration of distributed MBs (5.4-31.5 wt.% of loading hydroxyapatite on the membrane matrix) allowed the efficient sorption of Pb(II) with fast kinetics (20.0 min), excellent capacity (219.9 mg/g at pH 5.0, T 298 K), and favorable selectivity coefficients (2.76-6.79). The formation of minerals was dominant for the selective sorption of Pb(II) by combining the spectral analysis and quantitative determination. The surface complexation with O-/reductive N-species, the cation exchange with inorganic Ca2+, the electrostatic attraction with deprotonated O-, and the cation-π coordination with the aromatic carbon via the π-electrons should be not ignored for the capture of Pb(II). This work demonstrated the feasibility of electrospun CL/CS/MB membranes as a promising candidate for the remediation of aquatic pollutants.
The borehole coal samples of Dhulia North Block from the Rajmahal Basin, Eastern India, were systematically analyzed based on the chemical composition and concentration of major and trace elements (including rare earth elements, REEs) to assess the distribution of REEs and their environmental implications with utilization potential. The Dhulia North Block coals are characterized by the predominant major oxides of SiO2, Al2O3, and Fe2O3, accounting for 94% of the total ash composition, indicating the presence of quartz, clay-rich minerals, and pyrite. Compared with the average world coal ash, the total REE content in the analyzed samples ranged from 341.0 to 810.4 ppm, which is substantially higher. Hot humid climate conditions with intermediate igneous source rocks of the basin were demonstrated by the major oxide ratios (Al2O3/TiO2 < 20) and plots of TiO2 with Al2O3 and Zr. The redox-sensitive elements such as V, Ni, Cr, and Co found in the Dhulia North Block coal indicate that an oxic sedimentary environment existed in the basin when coal was formed. The low sulfur content (1% in most samples) indicates freshwater conditions in the basin at the time of organic matter deposition. The outlook coefficient (Coutl) varies between 0.7 and 1.6, indicating that the Dhulia North Block coals are a prospective source of REEs. The Dhulia North Block coals are characterized by low H/C and O/C atomic ratios ranging from 0.56 to 0.90 and 0.10 to 0.22, respectively, and contain type-III kerogens, indicating gas-prone source rock. Further, the basic-to-acid oxide ratio suggested that Dhulia North Block coals were suitable for utilization during combustion processes.
The study was conducted to evaluate the root, shoot and leaf callus cell regeneration and its biochemical properties like antioxidant, carbohydrate, pigment and mineral content from broccoli root, shoot and leaf cutting in vitro. An in vitro factorial experiment was carried out based on a Completely Randomized Design (CRD) with 5 replicates in tissue culture applying different IBA (0.25, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5 mg/l) and BAP (1 mg/l) concentrations using broccoli root tip and leaf cutting. The results showed that a higher callus weight was found in the cultured leaf cutting than in root tip cutting in the concentration of 1.0, 1.5 & 2.0 mg/l IBA + 1.0 mg/l BAP combination. The highest callus weight was found in the cultured leaf cutting than root tips cutting at the concentration of 1.5mg/l IBA+1.0 mg/l BAP. Furthermore, the highest inverted sugar and glucose, chlorophyll and nutrient content (K+, NO3- & Ca++), total phenol, flavonoid and total antioxidant were found in the concentration of 1.5mg/l IBA+1.0 mg/l BAP combination in both broccoli leaf and root cutting. The results seemed that it was best to use the combination of the IBA and BAP in the concentration of 1.0-2.0 mg/l and 1mg/l to regenerate root, leaf and callus cell proliferation of broccoli from the root tip and leaf cutting.
Environmental global issues affecting global warming, such as carbon dioxide (CO2), have attracted the attention of researchers around the world. This paper reviews and discusses the ground improvement and its contribution to reducing CO2 in the atmosphere. The approach is divided into three parts: the Streamlined Energy and Emissions Assessment Model (SEEAM), the replacement of soil stabilisation materials that lead to the emission of a large amount of CO2 with alternatives and mineral carbonation. A brief discussion about the first two is reviewed in this paper and a detailed discussion about mineral carbonation and its role in enhancing soil strength while absorbing a large amount of CO2. It is emphasised that natural mineral carbonation requires a very long time for a material to reach its full capacity to form CO2; as a result, different acceleration processes can be done from increasing pressure, temperature, the concentration of CO2 and the addition of various additives. In conclusion, it was found that magnesium is more attractive than calcium, and calcium is complicated in terms of strength behaviour. Magnesium has a larger capacity for CO2 sequestration and it has a greater potential to increase soil strength than calcium.
The oyster mushroom (Pleurotus spp.) is one of the most widely cultivated mushroom species globally. The present study investigated the effect of synbiotics on the growth and quality of Pleurotus ostreatus and Pleurotus pulmonarius. Different synbiotics formulations were applied by spraying mushroom samples daily and measuring their growth parameters, yield, biological efficiency, proximate composition, mineral content, total phenolic content (TPC), and diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity. Results demonstrated that the most significant yield of oyster mushrooms was harvested from synbiotics sprayed with inulin and Lactobacillus casei (56.92 g). Likewise, the highest biological efficiency obtained with a similar synbiotic was 12.65%. Combining inulin and L. casei was the most effective method of improving the mushrooms' growth performance and nutrient content in both samples. Furthermore, synbiotics that combined inulin and L. casei resulted in the highest TPC (20.550 mg gallic acid equivalent (GAE)/g dry extract (DE)) in white oyster mushrooms (P. ostreatus). In comparison, in grey mushroom (P. pulmonarius) the highest TPC was yielded by L. casei (1.098 mg GAE/g DE) followed by inulin and L. casei (1.079 mg GAE/g DE). The DPPH results indicated that the oyster mushroom could be an efficient antioxidant. The results revealed that applying synbiotics improved the mushrooms' quality by increasing their antioxidant capacity with higher amounts of phenolic compounds and offering better health benefits with the increased levels of mineral elements. Together, these studies demonstrated the potential of using synbiotics as a biofertilizer, which is helpful for mushroom cultivation; therefore, it might solve the challenge of inconsistent quality mushroom growers face.
The present study was undertaken to determine the content of six minerals, five trace elements, and ten pesticide residues in honeys originating from different regions of Malaysia. Calcium (Ca), magnesium (Mg), iron (Fe), and zinc (Zn) were analyzed by flame atomic absorption spectrometry (FAAS), while sodium (Na) and potassium (K) were analyzed by flame emission spectrometry (FAES). Trace elements such as arsenic (As), lead (Pb), cadmium (Cd), copper (Cu), and cobalt (Co) were analyzed by graphite furnace atomic absorption spectrometry (GFAAS) following the microwave digestion of honey. High mineral contents were observed in the investigated honeys with K, Na, Ca, and Fe being the most abundant elements (mean concentrations of 1349.34, 236.80, 183.67, and 162.31 mg/kg, resp.). The concentrations of the trace elements were within the recommended limits, indicating that the honeys were of good quality. Principal component analysis reveals good discrimination between the different honey samples. The pesticide analysis for the presence of organophosphorus and carbamates was performed by high performance liquid chromatography (HPLC). No pesticide residues were detected in any of the investigated honey samples, indicating that the honeys were pure. Our study reveals that Malaysian honeys are rich sources of minerals with trace elements present within permissible limits and that they are free from pesticide contamination.
A water extraction method has been used to extract plant proteins from the roots of Eurycoma longifolia harvested from Perak and Pahang, Malaysia. On the basis of the spectroscopic Bradford assay, Tongkat Ali Perak and Pahang contained 0.3868 and 0.9573 mg mL(-1) of crude protein, respectively. The crude proteins were separated by one dimensional 15% sodium dodecyl sulphate polyacrylamide gel electrophoresis into two (49.8 and 5.5 kD) and four (49.8, 24.7, 21.1 and 5.5 kD) protein spots for Tongkat Ali Perak and Pahang, respectively. Isoleucine was present in the highest concentration significantly. Both plant samples showed differences in the mineral and trace element profiles, but the minerals calcium, magnesium and potassium were present in the highest concentration. The highly concerned toxic metals such as arsenic and lead were not detected.
This study evaluated the effectiveness of Fenton's technique for the treatment of semi-aerobic landfill leachate collected from Pulau Burung Landfill Site (PBLS), Penang, Malaysia. The Fe2+ or Fe3+ as catalyst and H2O2 as oxidizing agent are commonly used for the classical Fenton's reaction. In present study, the effect of operating conditions such as pH, reaction time, molar ratio, agitation rate, feeding mode and Fenton reagent concentrations which are important parameters that affect the removal efficiencies of Fenton method were investigated. Under the most favorable conditions, the highest removals of 58.1 and 78.3% were observed for COD and color, respectively. In general, the best operating conditions were pH = 3, Fe = 560 mg L(-1), H2O2 = 1020 mg L(-1), H2O2/Fe2+ molar ratio = 3, agitation rate = 400 rpm and reaction time = 120 minutes. The results highlighted that stepwise addition of Fenton's reagent was more effective than adding the entire volume in a single step. Excessive hydrogen peroxide and iron have shown scavenging effects on hydroxyl radicals and reduced degradation of refractory organics in the landfill leachate.