scholarly journals Photocatalytic Degradation of Organic, Inorganic and Microbial Pollutants Present in Water by Novel Materials: A Critical Review and Present Update

2021 ◽  
Vol 33 (10) ◽  
pp. 2251-2259
Author(s):  
Elizabeth Kuruvilla ◽  
C. Freeda Christy ◽  
A. Samson Nesaraj

Presently water pollution is the one of the major threats faced by living things all over the world. The main cause of water pollution is its effect on the life of aquatic animals. Organic, inorganic, microbial and other pollutants often mix with water bodies mainly due to human activities. Because of the presence of pollutants in water, the amount of dissolved oxygen level can be decreased which in turn affect the survival of aquatic life. The pollutant water may enter the agriculture fields and damage the plants extensively. The methods, such as, coagulation, adsorption, foam floating, electrodialysis, capacitive deionization, etc. are presently employed to treat the waste water. Among these methods, heterogeneous photocatalytic degradation is considered to be a good method because of its low cost and environmental friendliness. In this review, the decontamination of different kinds of organic, inorganic and microbial contaminants in water with different photocatalysts process is presented.

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Abdul Rahman Hassan ◽  
Nor Amalina Ab Rahim ◽  
Mohd Talib Abdul Wahab ◽  
CE Noor Aien CE Mahmood ◽  
Engku Noraien ◽  
...  

Effective treatment of dyes wastewater is important to prevent water pollution. According to data by the Department of Environment (DOE) in 2017, 51 rivers have been polluted because of sewage, industry growth, livestock breeding and attitude of some irresponsible Malaysians that dump trash into river. One of the industries that contribute to river pollution is the batik industry. This is because batik processing activities have resulted in effluents containing chemicals streamed into the river and affecting aquatic life and human health as well. The main goals of this project is to produce a filter from available locally materials in solving polluted river water arising from batik wastewater. Along with the theme “from nature back to nature”, PadS-Clay Filter were prepared from 100% waste material such as paddy straw and clay according to designed formulation. Then, the dyes wastewater was flow on the PadS-Clay Filter and passed through the filter. The UV-Vis spectrophotometer was used to analyze the absorption and concentration of the filtered dyes wastewater. Based on the result, PadS-Clay 2 (PSC2) and PadS-Clay 3 (PSC 3) were the most effective designed formulation for dyes rejection and flux of dyes in treating dyes effluent as the percentage of the dyes rejection for all PSC2 were over than 90%.


Author(s):  
David Sedley

Stoicism is the Greek philosophical system founded by Zeno of Citium c.300 bc and developed by him and his successors into the most influential philosophy of the Hellenistic age. It views the world as permeated by rationality and divinely planned as the best possible organization of matter. Moral goodness and happiness are achieved, if at all, by replicating that perfect rationality in oneself, and by finding out and enacting one’s own assigned role in the cosmic scheme of things. The leading figures in classical, or early, Stoicism are the school’s first three heads: Zeno of Citium, Cleanthes and Chrysippus. It is above all the brilliant and indefatigable Chrysippus who can be credited with building Stoicism up into a truly comprehensive system. ‘Early Stoicism’ - the main topic of this entry - is in effect largely identical with his philosophy. No formal philosophical writings of the early Stoics survives intact. We are mainly dependent on isolated quotations and secondary reports, many of them hostile. Nevertheless, the system has been reconstructed in great detail, and, despite gaps and uncertainties, it does live up to its own self-description as a unified whole. It is divided into three main parts: physics, logic and ethics. The world is an ideally good organism, whose own rational soul governs it for the best. Any impression of imperfection arises from misleadingly viewing its parts (including ourselves) in isolation, as if one were to consider the interests of the foot in isolation from the needs of the whole body. The entire sequence of cosmic events is pre-ordained in every detail. Being the best possible sequence, it is repeated identically from one world phase to the next, with each phase ending in a conflagration followed by cosmic renewal. The causal nexus of ‘fate’ does not, however, pre-empt our individual responsibility for our actions. These remain ‘in our power’, because we, rather than external circumstances, are their principal causes, and in some appropriate sense it is ‘possible’ for us to do otherwise, even though it is predetermined that we will not. At the lowest level of physical analysis, the world and its contents consist of two coextensive principles: passive ‘matter’ and active ‘god’. At the lowest observable level, however, these are already constituted into the four elements earth, water, air and fire. Air and fire form an active and pervasive life force called pneuma or ‘breath’, which constitutes the qualities of all bodies and, in an especially rarefied form, serves as the souls of living things. ‘Being’ is a property of bodies alone, but most things are analysed as bodies - even moral qualities, sounds, seasons and so forth - since only bodies can causally interact. For example, justice is the soul in a certain condition, the soul itself being pneuma and hence a body. A scheme of four ontological categories is used to aid this kind of analysis. In addition, four incorporeals are acknowledged: place, void, time and the lekton (roughly, the expressed content of a sentence or predicate). Universals are sidelined as fictional thought constructs, albeit rather useful ones. The world is a physical continuum, infinitely divisible and unpunctuated by any void, although surrounded by an infinite void. Its perfect rationality, and hence the existence of an immanent god, are defended by various versions of the Argument from Design, with apparent imperfections explained away, for example, as blessings in disguise or unavoidable concomitants of the best possible structure. ‘Logic’ includes not only dialectic, which is the science of argument and hence logic in its modern sense, but also theory of knowledge, as well as primarily linguistic disciplines like rhetoric and grammar. Stoic inferential logic takes as its basic units not individual terms, as in Aristotelian logic, but whole propositions. Simple propositions are classified into types, and organized into complex propositions (for example, conditionals) and complete arguments. All arguments conform to, or are reducible to, five basic ‘indemonstrable’ argument formats. The study of logical puzzles is another central area of Stoic research. The Stoics doggedly defended, against attacks from the sceptical Academy, the conviction that cognitive certainty is achieved through ordinary sensory encounters, provided an entirely clear impression (phantasia) is attained. This, the ‘cognitive impression’ (phantasia katalēptikē), is one of such a nature that the information it conveys could not be false. These self-certifying impressions, along with the natural ‘preconceptions’ (prolēpseis) which constitute human reason, are criteria of truth, on which fully scientific knowledge (epistēmē) - possessed only by the wise - can eventually be built. Stoic ethics starts from oikeiōsis, our natural ‘appropriation’ first of ourselves and later of those around us, which makes other-concern integral to human nature. Certain conventionally prized items, like honour and health, are commended by nature and should be sought, but not for their own sake. They are instrumentally preferable, because learning to choose rationally between them is a step towards the eventual goal of ‘living in agreement with nature’. It is the coherence of one’s choices, not the attainment of their objects, that matters. The patterns of action which promote such a life were systematically codified as kathēkonta, ‘proper functions’. Virtue and vice are intellectual states. Vice is founded on ‘passions’: these are at root false value judgments, in which we lose rational control by overvaluing things which are in fact indifferent. Virtue, a set of sciences governing moral choice, is the one thing of intrinsic worth and therefore genuinely ‘good’. The wise are not only the sole possessors of virtue and happiness, but also, paradoxically, of the things people conventionally value - beauty, freedom, power, and so on. However geographically scattered, the wise form a true community or ‘city’, governed by natural law. The school’s later phases are the ‘middle Stoicism’ of Panaetius and Posidonius (second to first century bc) and the ‘Roman’ period (first to second century ad) represented for us by the predominantly ethical writings of Seneca, Epictetus and Marcus Aurelius.


2008 ◽  
Vol 27 (2) ◽  
pp. 133 ◽  
Author(s):  
O. P. Panwar ◽  
Anil Kumar ◽  
Rameshwar Ameta ◽  
Suresh C. Ameta

Water pollution due to effluents from dyes and printing industries poses a serious problem for aquatic life. Photocatalysis has attracted the attention of chemists all over the world because it is an efficient and ecofriendly process to combat the problem of water pollution. Photocatalytic bleaching of tolonium chloride on zirconium phosphate was carried out in presence of light. The progress of the reaction was monitored spectrophotometrically, and it follows pseudo first order kinetics. The effect of variation of different parameters, like concentration of tolonium chloride, pH, amount of semiconductor and light intensity on the rate of bleaching, was also studied. A tentative mechanism for the photocatalytic bleaching of tolonium chloride has been proposed.


Author(s):  
David Sedley

Stoicism is the Greek philosophical system founded by Zeno of Citium c.300 bc and developed by him and his successors into the most influential philosophy of the Hellenistic age. It views the world as permeated by rationality and divinely planned as the best possible organization of matter. Moral goodness and happiness are achieved, if at all, by replicating that perfect rationality in oneself, and by finding out and enacting one’s own assigned role in the cosmic scheme of things. The leading figures in classical, or early, Stoicism are the school’s first three heads: Zeno of Citium, Cleanthes and Chrysippus. It is above all the brilliant and indefatigable Chrysippus who can be credited with building Stoicism up into a truly comprehensive system. ‘Early Stoicism’ – the main topic of this entry – is in effect largely identical with his philosophy. No formal philosophical writings of the early Stoics survives intact. We are mainly dependent on isolated quotations and secondary reports, many of them hostile. Nevertheless, the system has been reconstructed in great detail, and, despite gaps and uncertainties, it does live up to its own self-description as a unified whole. It is divided into three main parts: physics, logic and ethics. The world is an ideally good organism, whose own rational soul governs it for the best. Any impression of imperfection arises from misleadingly viewing its parts (including ourselves) in isolation, as if one were to consider the interests of the foot in isolation from the needs of the whole body. The entire sequence of cosmic events is pre-ordained in every detail. Being the best possible sequence, it is repeated identically from one world phase to the next, with each phase ending in a conflagration followed by cosmic renewal. The causal nexus of ‘fate’ does not, however, pre-empt our individual responsibility for our actions. These remain ‘in our power’, because we, rather than external circumstances, are their principal causes, and in some appropriate sense it is ‘possible’ for us to do otherwise, even though it is predetermined that we will not. At the lowest level of physical analysis, the world and its contents consist of two coextensive principles: passive ‘matter’ and active ‘god’. At the lowest observable level, however, these are already constituted into the four elements earth, water, air and fire. Air and fire form an active and pervasive life force called pneuma or ‘breath’, which constitutes the qualities of all bodies and, in an especially rarefied form, serves as the souls of living things. ‘Being’ is a property of bodies alone, but most things are analysed as bodies – even moral qualities, sounds, seasons and so forth – since only bodies can causally interact. For example, justice is the soul in a certain condition, the soul itself being pneuma and hence a body. A scheme of four ontological categories is used to aid this kind of analysis. In addition, four incorporeals are acknowledged: place, void, time and the lekton (roughly, the expressed content of a sentence or predicate). Universals are sidelined as fictional thought constructs, albeit rather useful ones. The world is a physical continuum, infinitely divisible and unpunctuated by any void, although surrounded by an infinite void. Its perfect rationality, and hence the existence of an immanent god, are defended by various versions of the Argument from Design, with apparent imperfections explained away, for example, as blessings in disguise or unavoidable concomitants of the best possible structure. ‘Logic’ includes not only dialectic, which is the science of argument and hence logic in its modern sense, but also theory of knowledge, as well as primarily linguistic disciplines like rhetoric and grammar. Stoic inferential logic takes as its basic units not individual terms, as in Aristotelian logic, but whole propositions. Simple propositions are classified into types, and organized into complex propositions (for example, conditionals) and complete arguments. All arguments conform to, or are reducible to, five basic ‘indemonstrable’ argument formats. The study of logical puzzles is another central area of Stoic research. The Stoics doggedly defended, against attacks from the sceptical Academy, the conviction that cognitive certainty is achieved through ordinary sensory encounters, provided an entirely clear impression (phantasia) is attained. This, the ‘cognitive impression’ (phantasia katalēptikē), is one of such a nature that the information it conveys could not be false. These self-certifying impressions, along with the natural ‘preconceptions’ (prolēpseis) which constitute human reason, are criteria of truth, on which fully scientific knowledge (epistēmē) – possessed only by the wise – can eventually be built. Stoic ethics starts from oikeiōsis, our natural ‘appropriation’ first of ourselves and later of those around us, which makes other-concern integral to human nature. Certain conventionally prized items, like honour and health, are commended by nature and should be sought, but not for their own sake. They are instrumentally preferable, because learning to choose rationally between them is a step towards the eventual goal of ‘living in agreement with nature’. It is the coherence of one’s choices, not the attainment of their objects, that matters. The patterns of action which promote such a life were systematically codified as kathēkonta, ‘proper functions’. Virtue and vice are intellectual states. Vice is founded on ‘passions’: these are at root false value judgments, in which we lose rational control by overvaluing things which are in fact indifferent. Virtue, a set of sciences governing moral choice, is the one thing of intrinsic worth and therefore genuinely ‘good’. The wise are not only the sole possessors of virtue and happiness, but also, paradoxically, of the things people conventionally value – beauty, freedom, power, and so on. However geographically scattered, the wise form a true community or ‘city’, governed by natural law. The school’s later phases are the ‘middle Stoicism’ of Panaetius and Posidonius (second to first century bc) and the ‘Roman’ period (first to second century ad) represented for us by the predominantly ethical writings of Seneca, Epictetus and Marcus Aurelius.


1995 ◽  
Vol 31 (8) ◽  
pp. 59-66
Author(s):  
Pieter Huisman

In autumn 1971, water pollution and poison incidents caused death in the Rhine. Aquatic life disappeared. The rulling opinion was: Clean up the waste water and life will return. It proved to be a half-truth. After treatment of waste water some organisms returned, others, particularly the migratory fish, did not. Barrages and weirs have decimated the migratory fish. Waste water gave only the final knock-out for these species. Slowly understanding arose for a harmonization between human interests and the ecosystem. In course of time the Rhine-states replaced the one-sided promotion of individual interests by the concept of integrated water management, a prerequisite for sustainable development. This contribution reflects the process of changing minds.


HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 903D-903
Author(s):  
Robert D. Berghage ◽  
Dennis J. Wolnick ◽  
E. Jay Holcomb ◽  
John E. Erwin

The Internet offers many new and unique opportunities to disseminate information. The development of the World Wide Web (WWW) and information browsers like Netscap, Mosaic, and simple-to-use server software like MacHTTP provides means to allow low-cost access to information, including pictures and graphics previously unavailable to most people. The Pennsylvania State Univ. variety trial garden annually tests >1000 plants. Information is gathered on garden and pack performance, and photos of superior plants and varieties are taken. To provide wider access to this information, we have begun development of a Cyberspace trial garden on the internet. This server contains a wide variety of garden trial information developed from trials conducted in State College and Dauphin, Pa.. This server and a similar effort at Univ. of Minnesota are being constructed cooperatively. Hot links are provided between the server in Pennsylvania and the one in Minnesota, providing users with seamless access to information from both servers.


2021 ◽  
Vol 10 (1) ◽  
pp. 847-856
Author(s):  
Xiaowen Su ◽  
Zehua Wang ◽  
Yuan Huang ◽  
Zhenyu Miao ◽  
Shuhua Wang ◽  
...  

Abstract The hazard-free treatment of Cr(vi) ions is critical in modern industry. Photocatalytic reduction and detoxification are high-potential strategies. Photocatalysts with high efficiency, low cost, environmental friendliness, and easy mass products are required. In this study, we report a facile strategy using triethanolamine (TEOA) as a capping ligand to modify the surface of ZnO nanospheres. The experimental and theoretical results reveal that the presence of TEOA on the surface was beneficial for electron enrichment on Zn and hole transfer to TEOA and can photocatalytically reduce Cr(vi) by almost 100% in 5 min. The photocatalytic property of TEOA-modified ZnO could be renewed by the reabsorption of TEOA in solution. The great sedimental properties benefit photocatalyst recycling and renewal, which also provides high potential for water pollution and environmental emergency responses applications.


1997 ◽  
Vol 2 (4) ◽  
pp. 356-365 ◽  
Author(s):  
Fouad A-L.H. Abou-Hatab

This paper presents the case of psychology from a perspective not widely recognized by the West, namely, the Egyptian, Arab, and Islamic perspective. It discusses the introduction and development of psychology in this part of the world. Whenever such efforts are evaluated, six problems become apparent: (1) the one-way interaction with Western psychology; (2) the intellectual dependency; (3) the remote relationship with national heritage; (4) its irrelevance to cultural and social realities; (5) the inhibition of creativity; and (6) the loss of professional identity. Nevertheless, some major achievements are emphasized, and a four-facet look into the 21st century is proposed.


TEKNOSASTIK ◽  
2018 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Dina Amelia

There are two most inevitable issues on national literature, in this case Indonesian literature. First is the translation and the second is the standard of world literature. Can one speak for the other as a representative? Why is this representation matter? Does translation embody the voice of the represented? Without translation Indonesian literature cannot gain its recognition in world literature, yet, translation conveys the voice of other. In the case of production, publication, or distribution of Indonesian Literature to the world, translation works can be very beneficial. The position of Indonesian literature is as a part of world literature. The concept that the Western world should be the one who represent the subaltern can be overcome as long as the subaltern performs as the active speaker. If the subaltern remains silent then it means it allows the “representation” by the Western.


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