Polyethersulfone-Zno Mixed Matrix Hollow Fiber Membrane with Antifouling Properties for Humic Acid Removal

Satu teknik baru telah dicadangkan untuk mensintesis membran matrik bercampur (MM) berbentuk serat berongga (HF) dari formulasi yang ditentukan oleh membran kepingan rata. Untuk mencapai matlamat ini, membran kepingan rata MM yang berbeza telah disintesis daripada campuran “dope” yang mengandungi polietersulfona (PES), nanopartikel ZnO (ZnO-NPs), polivinilpirolidona (PVP), dan pelarut dimetilastamida (DMAc) menggunakan teknik pemisahan fasa. Hasil kajian ini telah menunjukkan bahawa ZnO-NPs telah meningkatkan kedua-dua hidrofilik dan kekasaran permukaan membran kepingan rata. Apabila ZnO-NPs ditambah, kebolehtelapan, penyingkiran asid humik (HA), dan sifat anti-pengotoran membran juga dipertingkatkan. Penambahan ZnO-NPs yang hidrofilik ke dalam PES boleh mengurangkan kotoran asid humik dengan syarat NPs diagih dengan seragam di dalam matrik polimer. Keputusan membran kepingan rata seterusnya telah menunjukkan bahawa nisbah ZnO-NPs kepada PVP hendaklah sama atau lebih daripada satu untuk memastikan agihan ZnO-NPs yang baik dalam matrik PES. Kontur dalaman membran serat berongga (HF) boleh diubah oleh keadaan putaran dan juga masa putaran. Formulasi optimum yang diperolehi telah digunakan dalam pembangunan membran MM HF dengan kontur dalaman yang dikawal sepenuhnya. Kajian kestabilan struktur membran HF dilakukan berdasarkan masa residensi di kawasan ruang udara (Rtm). Ketetapan kontur dalaman telah terbukti menjadi bulat sepenuhnya dengan peningkatan Rtm. Ini mungkin disebabkan oleh peningkatan dalam pemindahan jisim dalaman, kestabilan polimer, orientasi molekul, dan pelepasan tekanan. Kajian ini telah menunjukkan bahawa Rtm kritikal yang menghasilkan kontur dalaman bulat sepenuhnya adalah 0.67 s. Kemudian, membran MM HF telah disintesis pada Rtm yang sama dengan 0.82 s dan diuji menggunakan larutan sintetik HA. Penghasilan membran MM HF yang terhasil menunjukkan peningkatan dalam sifat hidrofilik, kebolehtelapan, dan sifat anti-pengotoran semasa penurasan HA. Walau bagaimanapun, sifat-sifat anti-pengotoran adalah lebih rendah daripada PES asli kerana kehadiran CaCl2. Prestasi penyingkiran membran MM HF semasa penurasan air sungai menunjukkan bahawa penggabungan 0.5 wt.% ZnONPs dapat menyahkan TOC pada kadar 26.15% berbanding hanya 6.92% menggunakan PES asli. Semasa penurasan air sungai dalam jangka masa yang lama, nisbah pemulihan fluks utama (FRR) sebanyak 96.80 % diperolehi pada 0.5 wt.% ZnO-NPs berbanding hanya 75.55% daripada FRR untuk PES asli. Ini menunjukkan bahawa membran MM HF yang diubahsuai telah berjaya dihasilkan untuk menyingkirkan HA. ________________________________________________________________________________________________________________________ A new technique was proposed to synthesize mixed matrix (MM) hollow fiber (HF) membrane from pre-determined MM flat sheet membrane formulation. To achieve this goal, different MM flat sheet membranes were synthesized from dope solution containing polyethersulfone (PES), ZnO nanoparticles (ZnO-NPs), polyvinylpyrrolidone (PVP), and dimethylacetamide (DMAc) solvent using phase separation technique. It was shown that the ZnO-NPs increased both membrane hydrophilicity and surface roughness of flat sheet membrane. Upon the addition of ZnO-NPs, the permeability, humic acid (HA) rejection, and anti-fouling property of membrane were also enhanced. The addition of hydrophilic ZnO-NPs to PES can alleviate the humic acid fouling provided the NPs are well dispersed inside the polymeric matrix. Flat sheet membrane results further indicated that the ZnO-NPs to PVP ratio should be equal to or more than unity to ensure good dispersion of ZnONPs inside PES matrix. Hollow fiber (HF) membrane inner contour could be varied by both spinning conditions as well as during the spinning time. The optimum formulation obtained was used in the development of MM HF membrane with fully controlled inner contour. Structural stability study of HF membrane was performed based on the residence time in the air gap region (Rtm). The regularity of the inner contour was proved to be fully circular with increasing Rtm. This might be due to enhancement in the internal mass transfer, polymer relaxation, molecular orientation, and stress release. It was shown that the critical Rtm that produced fully circular inner contour was 0.67 s. Subsequently, MM HF membrane was synthesized at Rtm equal to 0.82 s and tested for synthetic HA solution. The MM HF membrane showed enhancement in hydrophilicity, permeability, and anti-fouling property during HA filtration. However, the membrane antifouling properties were lower than the pristine PES due to the presence of CaCl2. The rejection performance of MM HF membranes during filtration of river water indicated that incorporation of 0.5 wt.% of ZnO-NPs was able to remove 26.15 % of the TOC compared to only 6.92 % for pristine PES. During long hours of river water filtration, ultimate flux recovery ratio (FRR) of 96.8 % was obtained at 0.5 wt.% of ZnO-NPs compared with only 75.55 % of FRR for the pristine PES. This showed that the modified MM HF membranes had been successfully developed for humic acid removal

Interpretation of IUE and other spectra of planetary nebulae

The current status of observations of planetary nebulae and their central stars is presented. Particular attention is given to ultraviolet observations secured with the IUE satellite. The physical processes occurring in these objects are discussed, with emphasis on the atomic data. The planetary nebulae SwSt 1, IC 2501, and NGC 4361 have been observed with the IUE satellite. These observations have been combined with observations made by other workers at optical, infrared, and radio wavelengths in order to determine physical conditions in these objects. The electron density in the compact nebula SwSt 1, determined from the C III λλ1907/1909 line ratio, is high (~10(^5) cm(^-3)), consistent with the high emission measure determined from radio observations. The C/0 abundance ratio in this nebula is found to be 1. The ultraviolet observations are therefore consistent with the interpretation of the infrared observations, namely, that objects with SiC are carbon rich. An ionization model of NGC 4361 is presented which fits the observed ultraviolet and optical line fluxes well. It is found that the inclusion in the model nebula of charge exchange and dielectronic recombination processes greatly improves the computed ionization and thermal structure of the nebula

Scheduling Security Model for a Cloud Environment

Context: Scheduling in the cloud is a complex task due to the number and variety of resources available and the volatility of usage-patterns of resources considering that the resource setting is on the service provider. This is compounded further when security issues and Quality of Service (QoS) are also factored in. Aim: The aim of this research is to address limitations and gaps in current approaches of resource scheduling in cloud computing by developing a Scheduling Security Model (SSM). Method: Considering security as a key element that cloud services rely on which affects the services performance, cost and time concerns within the security constraints of the cloud service. Furthermore, this research will investigate and define the considerable challenges facing trusted and cost-effective resource scheduling in cloud computing environments. The SSM analyses the customer requirements for a service then works to schedule all tasks submitted to run over available resources depending on the security level. It then uses the SSM Algorithm and the Fast-Track technique to reduce the cost and the overall waiting time. Results: The worked examples of the SSM with different scenarios and comparing the SSM against other approaches in the same field show that the SSM can meet the customer requirements for cost effective and the QoS required. Conclusions: The advantages from the results show that the SSM can reduce the overall service cost compared to other approaches

The impact of board and ownership on the value of firms listed on FTSE Bursa Malaysia EMAS Shariah index / Adnan Ameen Abdullah Bakather

The flourishing of the Islamic financial industry has been widely recognized worldwide. However, the corporate governance of such an industry is still questionable, in particular, the Islamic equity markets. The review of literature showed the corporate governance of Shariah approved firms has only been empirically tested in few studies. These studies have failed to produce consistent evidence on the impact of governance mechanisms on these Shariah approved firms. In addition, these studies ignored the Islamic perspective of corporate governance. The study mainly investigates the relationship between the corporate governance mechanisms and value of firms listed on FTSE Bursa Malaysia EMAS Shariah Index over the period of 2007 to 2009. In addition, the current study examines the moderating effects of corporate social performance and corporate financial performance on the relationship between these mechanisms and firm valuation. Several statistical techniques have been adopted in order to test the study hypotheses. These include the descriptive statistics, univariate tests and the regression analysis. The Ordinary Least Squares (OLS) regression analysis within the framework of the Moderated Multiple Regression (MMR) framework has been used to test the hypotheses

HAMKA’s concept of moderation an analysis

Islam advocates balance between spiritual, emotional, and cognitive aspects of human life. Any imbalance between these aspects may tarnish the real image of Islam. Concentration on the informational and cognitive aspects of the religion and disregard of the endeavor towards excellence will create imbalance between ÊmÉn, islÉm and iÍsÉn. Likewise, Islam strikes a balance between individualism and collectivism. Man’s relationship with his Creator is the basis of moral attitude of man towards his fellow men namely, interpersonalrelationship. This is the real basis of Islamic morality or ethical system. Islam enjoins wisdom, balance, moderation and tolerance in all affairs. Moderation or balance is not only as general characteristic of Islam, but it is its fundamental landmark. This article attempts to analyze HAMKA’s Concept of Moderation based on his book “Falsafah Hidup” (Philosophy of life)

Cabaran dalam komunikasi sukarelawanan

Encik Khoo Yeoh Gan Hong, Pengerusi Settlement Youth Council bagi penggal 1956-1957, dalam ucapan sulung beliau selepas dipilih selaku Pengerusi pada 5 Mei 1957 menyatakan bahawa, “Within a few months we shall welcome a new era in the history of this country. We must be prepared to face and accept greater challenges and responsibilities. To this end let us pray for a strong back rather than for a light burden. As youth leaders and workers of all races, classes and creeds, may we be given the strength to spread the spirit of the brotherhood, goodwill and tolerance and may our personal examples be worthy of emulation” (Misni Surif, Mohamed Maliki Mohamed Rapiee & Ishak Saat (2008) 60 Tahun Perjalanan Majlis Belia Negeri Pulau Pinang, 1948-2008.

TANTANGAN DAN PELUANG PENDIDIKAN QURAN DI KOTA BESAR

Artikel ini menyelidiki dinamika pendidikan Quran di kota besar yang serba sibuk dan multikultural. Dalam konteks urbanisasi yang cepat, tantangan utama seperti aksesibilitas yang terbatas, kesibukan sehari-hari, dan diversitas budaya menjadi sorotan utama. Namun, dalam tantangan ini juga terungkap peluang yang menjanjikan. Melalui pendekatan penelitian kualitatif yang melibatkan wawancara mendalam dan analisis isi, artikel ini mengidentifikasi tantangan kunci yang dihadapi pendidikan Quran di kota besar, termasuk dampak urbanisasi pada kehidupan sehari-hari individu. Di samping itu, artikel ini juga menggali peluang seperti penggunaan teknologi modern, integrasi dengan pendidikan sekuler, dan kolaborasi komunitas yang dapat memperkuat pendidikan Quran dalam konteks perkotaan yang beragam. Penelitian ini menghasilkan wawasan yang mendalam tentang bagaimana pendidikan Quran dapat beradaptasi dan berkembang di masyarakat perkotaan yang terus berubah, dan mengilustrasikan upaya yang dapat diambil untuk mengatasi tantangan serta memanfaatkan peluang yang ada

Detection of SQL Injection Attacks Based on Supervised Machine Learning Algorithms: A Review

In the ever-changing world of cybersecurity, it is becoming more important to ensure integrity of web applications as well as securing sensitive data. Among a variety of vulnerabilities, SQL injection is considered a significant risk with severe consequences. Addressing this crucial threat has always attracted the researchers to explore various approaches to identify and detect SQL injection attacks. The machine learning has captured the attention of the researchers to explore its potential due to its success in several different fields and the limitation of other rule-based approaches. This study provides a comprehensive review on a variety of the most recent researches that have been carried out using supervised learning algorithms. The study reveals that machine learning has a huge potential in the process of identification and detection of SQL injection attacks