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The content of amino groups in chitosan becomes the main cause of its differences from chitin in the context of structures and properties such as their chelation, flocculation, and biological functions. Furthermore, the random distribution of chitosan makes it easier to generate intra- and inter-molecular hydrogen bonds. Also, the existence of two hydroxyl groups and one primary amine group in chitosan, which can donate a free pair of electrons, make it soluble in diluted aqueous acetic solvents, and allow the formation of the coordination bonds that increase the possibilities for chemical modification. Its modification includes the incorporation of hydrophobic groups. Therefore, this paper reviews the properties of chitosan.

Biosensors are in principle fabricated by immobilized biomaterials on a detector membrane and combining them with electrochemical equipment. The applications of enzyme-based biosensors can be explored such as in the process of gas detection, medicine, pathogen detection and detection of toxic levels of substances before and after bioremediation. In this study, H2O2 detection was performed using HRP/PANI, HRP/PPY, HRP/PT and HRP/PT/PPY/PANI layers. The HRP/PANI layer from Variable Pressure Scanning Electron Microscopy (VPSEM) image exhibited a dry surface. The HRP/PPY layer exhibited a surface with agglomerate molecules. The HRP/PT layer, on the hand, exhibited a layer surface with almost the same molecular size. This is confirmed by the higher surface roughness value for HRP/PPY compared to other layers obtained via characterization with Atomic Force Microscopy (AFM). The increasing current response for all three layers was arranged in HRP/PANI> HRP/PT> HRP/PPY. VPSEM and AFM images exhibited surfaces with molecules being in an agglomeration state after the H2O2 detection process. In terms of current response, the response rate of H2O2 on the surface of the HRP/PT/PPY/PANI electrode caused the current response obtained to be fast. The roughness value increased with time due to the reaction that took place between the surface of the HRP/PT/PPY/PANI layer with H2O2. The day-based current response showed that day 1 to day 14 exhibited a uniform graph pattern but from day 21 to day 30 there was a change in the graph pattern due to the HRP/PT/PPY/PANI layer undergoing degradation. The activity of the HRP enzyme was studied by looking at its absorption effect for 30 days. From day 1 to day 14, there was a difference in the overall rate of absorption. However, from day 21 to day 30, the rate of absorption remained constant which explains the slowing down of HRP activity &nbsp

The wood has unique structure and excellent mechanical properties. Wood is important natural source for human civilization. Wood is anisotropy structure. Wood was the important material and natural resource in human civilization. Wood is widely used in many sectors such as building, fuel, tools and other. In the ancient, wood played an important role in human cultural, economic, act and building. As a natural and sustainable material, wood has excellent mechanical properties cause by unique structures relative to its cost. Wood due to its natural growth can define as renewable and sustainable material. Due to the hierarchical and anisotropy structure, wood have properties of high strength, good durability, high moisture content and high strength. Wood is porous and fibrous structural tissue of wood. Roots and stems of wood made by natural cellulose fibres growing upward all the way to the top of canopy. This paper will present a preliminary review about the future of transparent wood.

Brachytherapy is a type of radiation that involves precisely placing radioactive sources directly into or close to the tumour. This treatment is recommended for people suffering from many forms of cancer. It is an ideal tool for delivering extremely high dosages to the tumour while limiting the risk of normal tissue consequences. Physicians from a variety of disciplines may be involved in either referring to or placing brachytherapy. Brachytherapy is required for many patients as either a main treatment or as part of their oncologic care. Brachytherapy can be used to treat a wide range of tumour locations, including gynaecological, urologic, rectal, cutaneous, and breast malignancies. In most brachytherapy treatments, a radiation oncologist, called a radiation oncologist, relies on imaging techniques such as CT scans and ultrasound during the planning and delivery of brachytherapy to accurately identify encapsulated materials. Let it be placed. By using implants, it is possible to deliver a higher radiation dose to a limited area than conventional external beam radiotherapy. This may be more effective at destroying cancer cells while causing minimal damage to surrounding normal tissue is placed in patients are sedated for all these procedures.

Conducting polymers have previously been employed in biosensors because they may be used as immobilisation matrices as well as redox systems. Also have numerous uses in medical, pharmacy, environmental monitoring, food and process control. The conductivity of polyaniline-based compositions may be precisely regulated over a broad range. Polyaniline is ease to synthesis, has high conductivity and good performance in biosensor applications. However, polyaniline is not entirely perfect because of its poor solubility in many solvents and low adhesion to different substrate. In this study, hydrochloric acid (HCl) and sulphuric acid (H2SO4) were prepared with different concentration (0.2M, 0.4M, 0.6M, 0.8, 1.0M) for doping process of polyaniline. Fourier-transform Spectroscopy (FTIR), Ultraviolet Spectroscopy (UV-Vis) and Scanning Electron Microscopy (SEM) were used to characterize the properties and morphology of the polyaniline. Four point probe was used to identify the conductivity of the polyaniline sample. FTIR shows a shift peak at benzenoid rings and quioniod rings. Both acids represent that 1.0 M have high absorbance properties. While SEM shows significant different of agglomeration rate for HCl compared to H2SO4. Lastly, the results showed that the conductivity increasing when the concentration of acids increasing. Doping process helps in enhancing the conductivity properties of polyaniline for biosensor application.

The pandemic COVID-19 crisis have affected globally in every areas of economic businesses as well as the management of human resource in organization. This studies aims to explore in the challenges faced by Human Resource Management (HRM) functions during the COVID-19 crisis. The method used for this study is by reviewing literature of previous study by exploring how COVID -19 impacted HRM and how HRM cope with the situation. It is revealed that the pandemic COVID -19 crisis have impacted and give challenges to the HRM function in an organization. In conclusion, the challenges arise from these pandemic has disrupted human resource strategies in managing the workforce.

The most important commodity from Malaysia is the oil palm tree, which has helped to reshape the agricultural and economic landscape. Oil palm tree pieces are used to make cellulose biomass. However, the current state of oil palm waste has created a significant disposal issue. Waste management is based on the ideas of waste minimization and recycling. In order to achieve energy efficient and environmentally friendly, oil palm tree is the best choice. due to some problems occurring from previous studies which is fiberglass, cellulose has been made a new idea for insulation. The effectiveness of the insulation method is measured in R-value. R-value determines the ability of heat to pass through the insulator. If the fiberglass has been installed for a long period of time, the R-value will decrease as the insulation settles or compacts. The purpose of this study was to study the effect of ionizing radiation on cellulose using time-varying method, to identify the chemical and physical properties of oil palm tree and lastly, to identify the resistivity for cement and cellulose mixture. In view of the fact, cellulose contain no oxygen due to material’s compactness. Considering, there is no oxygen in the materials, the amount of damage cause by fire can be reduced. In this research, it will undergo pre- treatment method to obtain the cellulose. After that, the sample will go through four-point probe method to earn the resistivity. Considering that the finding has been proven by the result of the resistivity. In summation, the cellulose from oil palm tree can be propose as the new insulating material in the building structure.

Today's ink is not a good choice for long-term use because it contains higher levels of volatile organic compounds (VOCs). Surprisingly, the notion of making ink out of vegetable oils was one of the best inventions for the development of ink in the world because it was an environmentally friendly ink. The impact of radiation on the qualities of peanut oil and its utility as a consumer product will be discussed and information will be provided in this review study. The qualities of the oil will be improved by using radiation, and it can be used in community products. Nonetheless, while this sort of ink made from peanut oil is less harmful, its capabilities needed to be enhanced.

Concrete is a combination of cement, fine aggregate, coarse aggregate, and water. Concrete has a high shielding potential against gamma radiation from radioactive source. Concretes having a higher attenuation coefficient may be produced by varying the additives of various specific densities to increase the shielding performance. This study uses a cogon grass fiber, an invasive and unwanted grass due to their ability to grow, and disrupt desirable vegetation efficiently as a reinforcement material mixed into the concrete composite to observe its performance in radiation shielding. Natural fiber is known to have a tolerance to post splitting, high energy absorption and increased fatigue resistance of cement-based composites. Cogon grass fibers are use with different percentages of 0%, 0.5%, 1.0% and 1.5% fiber content with four different thicknesses. In this study, the chemical and physical properties of cogon grass were characterized by the hydrolysis process (Chesson Method) and Atomic Force Microscopy (AFM), respectively. The effect of different percentage of cogon grass fiber in concrete with different thickness to linear attenuation coefficient, the difference of linear attenuation coefficient value between lead concrete and cogon grass fiber concrete and half value layer (HVL) were also investigated. The possibility of using cogon grass natural fiber as a block of concrete for gamma radiation shielding was also evaluated based on the results obtained in this study. The results show that the hemicellulose, cellulose and lignin content of raw cogon grass fiber were 27.60%, 36.62% and 6.11%, respectively. AFM micrograph of cogon grass showed a blocky and rough surface. The calculated linear attenuation coefficient of cogon grass fiber showed an increase with the increase of fiber content and thickness. However, lead concrete showed a higher attenuation coefficient and lower HVL value compared to cogon grass fiber. Despite that, cogon grass fiber concrete may have t

Living in the fast-developing world, wastes and residues from the various industrial sectors are increasing day by day in myriad quantity which strongly affected our health ecosystems and eventually the human community. Realizing this fact, there is demand for each agro-industrial sector for safe utilization of agro-materials through wastes recycling.  These residues constituent various valuable by-products can be exploited into biogas, bioenergy, biofuel, biocomposite and biomaterials which are applied into textiles industries, food safety and packaging, medical tool and many more. The demands of the present generation can be meet and fulfill without compromising the future generation sources. Hence, there is in-depth attention and studies of agro-industrial biorefinery as well as their recycling methods. This article presents a review on the classification of these residues, several refinery products of agro-industrial wastes and their challenges needed to overcome in the future. &nbsp

Qai’lullah or napping is a phenomenon that is widely practiced in the world. Islam advocates mid-day napping as it is primarily practiced by the Prophet Muhammad (pbuh). Scientists and scholars also acknowledge the benefits beyond this practice after various research and studies done. Hence, this article emphasizes topic of sleep in Islamic insight, their stages of sleeps according to Quran and the practiced of Qai’lullah or mid-day napping. The effect associated with Qai’lullah are also being reviewed including improved the neurocognitive performance, alertness, recover the loss night sleep and enhanced the quality, increased memory consolidation as well as interrelation of light exposure to circadian rhythm of human being.

Selection of suitable shielding materials depends on the type, intensity and energy of radiation source, as well as the shielding properties such as mechanical strength, economic preparation and resistance to radiation damage. When compared to ordinary concrete, the addition of some materials with various fractions in the composition of concrete has provided concrete forms more efficient for gamma ray shielding. Concrete has proven to be an tremendous and adaptable shielding material with a well-established linear attenuation coefficient for gamma rays and neutrons. The objectives of this study is to determine the exact composition of concrete constituents and its density. Concrete samples were prepared by mixing cement, water, aggregate and additive with different composition and densities. Density was increases by decreasing the aggregates percent and increasing the additives such as lead oxide. Sample will be compacting to forming a solid material through pelleting and sintering process. Finally, it will undergo for radiation attenuation test. It was found that, substitution of lead oxide by aggregate causes increasing in the specific density and compressive strength of the concrete.

The synthetic plastic made by petroleum-based resources are commonly used by the society for their daily activities such as shopping bags, food packaging and drinking bottles. These plastics ease our daily task, however the arising amounts of their waste lead to the overloading in land and affect the environment and ecosystems due to their non-biodegradable properties. On the other side, orange juice production generates about 50-60%of residues from initial the mass that are underutilized. The orange wastes constitute a valuable bioactive compound such as pectin and cellulose, potential for bioplastic application. Thus, orange peels reinforced by the epoxy composites are investigated for the production of bio-based polymer utilized ferrite magnetic powder as filler.

Wood have been main of raw material for paper production around world. This lead to negative effect for our forest and environment. Aim of this paper is to review other suitable non-wood to replace wood as main material for paper production. Main material in this review are banana fiber and pineapple leaves.

A fault tree described the logical relationship between events and causes. This method shows significant success in analyzing the root cause of an accident. This paper will review the basics of the Fault Tree (FT) method including the structure, factors that contribute and FT application.

This paper reviews about the future of pineapple leaf paper by focusing on the properties and potential of pineapple leaf paper. Besides that, environmental issues and quality of pineapple leaf paper as compared with the existing paper in market are also discussed.

Earmuffs are objects designed to cover a person's ears for hearing protection when doing the harsh work field or for warmth on the cool environment . They consist of a thermoplastic or metal head-band, that fits over the top or back of the head, and a cushion or cup at each end, to cover the external ears.

Safety product is created for workers, students, people and society to prevent from dangerous, harmful, injured also risks situation that can be occurs before, during and after works. The materials to produce the safety product must be strong, hard, good resistance, fast treatment and others characteristic that can be protect and prevent the user from the dangerous. Sometimes, the cost to produce the safety product is expensive because of the material to make the safety product become the good products.

Bouffant cap is safety product like a loose cap net that can secured around the head with an elastic. This product is usually used in cleanrooms, food service and medical field. According to Personal protective equipment, frequently referred to as "PPE," is equipment worn to minimize exposure to risks causing severe injuries and accident in the workplace. These accidents and diseases may lead from chemical, radiological, physical, electrical, mechanical or other dangers in the workplace. The personal protective equipment should be designed for safety, can maintain cleanliness and also reliable fashion. It should be comfortably to wear and safely covered.

In many industrial working environments, for example, mining, power, construction, and forestry, the risk of head injury that is totally encased in bone to workers is always being heard. The importance of wearing safety helmet is being supported by OSHA Standard 1910.135 which states that “The employer shall ensure that each affected employee wears a protective helmet when working in areas wherever there's a possible for injury to the top from falling objects.” In addition, the survey of accidents and injuries conducted by the American Bureau of Labor Statistics (BLS) resulted that most workers who were not wearing head protection suffered impact injuries to the head (Cynthia L Roth, 2011). There are two different type of impact protection which is type I and type II. Type I is intended to reduce the force of impact resulting from a blow only to the top of the head. This form of impact, for example, may result from a hammer or nail gun falling from above. For the type II, it is intended to reduce the force of lateral impact resulting from a blow which may be received off-center, from the side, or to the top of the head. This form of impact, for instance, could result from contact with the sharp corner of a facet beam. The most common combination is white for managers, architects, engineers, foremen or supervisors. Other onerous hat designs is also needed for a job; brown fibreglass onerous hats area unit worn by welders and different employees for top heat applications. Green typically signifies a security inspector, however is additionally used for brand new employees.