Adunan Getah Asli/Polistirena (NR/PS) Bersama HVA-2 sebagai Agen Taut Silangan

Adunan getah asli (NR) dan polistirena (PS) telah disediakan dengan kaedah leburan menggunakan mesin plasticorder pada komposisi yang berlainan. Adunan telah dilakukan pada kadar rpm, suhu 120°C dalam masa 15 minit. Penambahan m-fenilenabismaleimida (HVA-2) dan getah asli cecair (LNR) ke dalam adunan pada komposisi NR/PS 60/40 dan 70/30, didapati meningkatkan sifat-sifat mekanik adunan. HVA-2 dipercayai berkeupayaan menyeragamkan pembentukan taut silangan terutamanya dalam fasa getah. Komposisi optimum HVA-2 dan LNR bagi adunan NR/PS 60/40 adalah masing-masing 1.2 -1.3 phr dan 5% LNR. Bagi adunan 70/30, kepekatan optimum adalah 1.6 - 1.7 phr dan 10% LNR

Methyl 3-acet­oxy-3-dehydroxy­ursolate

Four of the five six-membered rings of the title penta­cyclic triterpene, C33H52O4, adopt chair conformations; the fifth, which has a C=C double bond, adopts an approximate envelope conformation

Methyl 3-dehydr­oxy-3-oxoursolate

Four of the five six-membered rings of the title penta­cylic triterpene, C31H48O3, adopt chair conformations; the fifth, which has a C=C double bond, adopts an approximate envelope conformation

Cardiovascular Activity of Labdane Diterpenes from Andrographis paniculata in Isolated Rat Hearts

The dichloromethane (DCM) extract of Andrographis paniculata Nees was tested for cardiovascular activity. The extract significantly reduced coronary perfusion pressure by up to 24.5 ± 3.0 mm Hg at a 3 mg dose and also reduced heart rate by up to 49.5 ± 11.4 beats/minute at this dose. Five labdane diterpenes, 14-deoxy-12-hydroxyandrographolide (1), 14-deoxy-11,12-didehydroandrographolide (2), 14-deoxyandrographolide (3), andrographolide (4), and neoandrographolide (5), were isolated from the aerial parts of this medicinal plant. Bioassay-guided studies using animal model showed that compounds, (2) and (3) were responsible for the coronary vasodilatation. This study also showed that andrographolide (4), the major labdane diterpene in this plant, has minimal effects on the heart

Islamic Prayer, Spirituality and Productivity: An Exploratory Conceptual Analysis

Prayer plays a noteworthy role in Muslims daily lives. Quran and Sunnah testify that regular prayers can boost one’s health, can remove the level of stress, and may make one more productive and vigour. Such findings also noticed by medical and psychological experts, and likewise many contemporary research have shown wide-ranging outcomes in terms of improved wellbeing when prayer is done with sincere devotion. Nevertheless what is lacking is that the policy makers in the Islamic world need to initiate whether there exist any linkages between prayer and productivity, which needs to be appreciated more by them, as well as by Islamic economists and social scientists, Islamic business professionals and Islamic jurists, and then through a concerted effort and dynamic fact finding mission and verification to ascertain the Qur’anic beliefs in our daily lives. This studies using descriptive analysis to explain the linkage between the Islamic prayer and productivityDOI: 10.15408/aiq.v8i2.316

Effect of precipitation route on the properties of antimony trioxide

Antimony trioxide was prepared, using antimony potassium tartarate as starting material, via forward and reverse precipitation technique. The characteristics of the resulting antimony oxides were determined by BET surface area method, differential thermogravimetry analysis (DTG), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and SEM. The DTG curves for all uncalcined samples showed only a single endothermic peak which indicated that the sample is antimony trioxide. Unlike forward precipitation technique which resulted in a single antimony trioxide phase which is senarmontite, reverse precipitation technique produced antimony trioxide with both senarmontite and valentinite phase. Upon calcinations at 723 K, a small amount of Sb2O4 with cervantite phase was formed at the expense of Sb2O3 senarmontite phase as detected from the XRD pattern and infrared spectrum of RSb. The effect of preparation route on the properties of the antimony trioxide produced was clearly demonstrated

Educators' perception towards automation of curriculum design process for institution of higher learning in Malaysia

Curriculum design is an important phase in curriculum development process. Curriculum design precedes its submission to national regulatory body for approval. Curriculum design process plays an important role in helping educators to produce curriculum that is incompliance with the program standards and guidelines set by national regulatory body. The traditional approach requires much cumbersome manual iteration, making the process longer and error-prone. It is believed that automating the design process by utilizing advanced IT/ICT technologies helps to increase effectiveness and efficiency. Hence, a preliminary study is conducted to determine the perception of needs relative to automation of curriculum design process and current obstacles or issues during the design process. Five experienced educators from both private and public Institutions of Higher Learning in Malaysia who are involved in curriculum design are interviewed. The design process may vary from one university to another, as well as from one faculty to another. The purpose of this study serves as a preliminary study. This preliminary study has been conducted based on the authors' prior work. This study creates an awareness of the extent of needs for design process automation supported by IT/ICT. These needs may be reflected in the planning of future research

Users' verification of information system curriculum design model

Users’ Involvement is very crucial in any model or system development in the domain of information systems. In a preliminary study conducted earlier, the findings shown that users faced difficulties during curriculum design process. Consequently, a model namely Information System Curriculum Design Model is proposed. The purpose of this paper is to perform users’ verification to ensure the proposed model meet requirements of users who are also called curriculum designers. Survey is conducted to gather responses from 90 curriculum designers in 20 Institution of Higher Learning (IHL). The survey findings indicate that each component of the proposed model is perceived important. Once the proposed model is verified, it is converted to a prototype for further testing in the future

Prediction Of Cutting Force In End Milling Of Inconel 718

This paper presents the effect of cutting parameters on the cutting force when machining Inconel 718. Response surface methodology (RSM) was used in the experiment, and a Box–Behnken design was employed to identify the cause and effect of the relationship between the four cutting parameters (cutting speed, feed rate, depth of cut and width of cut) and cutting force. The ball-nose type of end mill with donwmill approach was maitained througout the experiment. The forces were measured using kistler dynamometer during straight line machining strategy. The result shows that the radial depth of cut was the dominating factor controlling cutting force, it was followed by axial depth of cut and feed rate. The prediction cutting force model was developed with the average error between the predicted and actual cutting force was less than 3%