Pesticides contamination is a wide spread source of environmental pollution and a matter of concern all over the world. In recent decades, the use of pesticides for agricultural purposes has steadily increased. Surface and ground water contamination due to extensive use of pesticides is a serious threat to the environment and human health. Pesticides are very toxic compounds causing various diseases. Therefore, in this research work, efforts have been made to determine various chlorinated pesticides contamination in water samples of selected areas of Khyber Pukhtoon Khwa, Pakistan. The determination of 20 chlorinated pesticides have been performed in surface and ground water samples collected from different districts (Peshawar, Mardan, Sawabi and Charsadda) of Khyber Pukhtoon Khawa, Pakistan. A total of 239 water samples (157 surface and 82 ground water samples) were collected from various locations of selected areas. The number of surface water samples, collected from Peshawar, Mardan, Charsadda and Sawabi districts were 59, 42, 30 and 26 samples, respectively. Similarly, 29, 24 and 29 ground water samples were collected from Peshawar, Charsadda and Mardan districts, respectively. Solid phase microextraction (SPME) technique was used for various pesticides extraction from water samples. Chlorinated pesticides were determined in water samples using SPME coupled with gas chromatography and electron captured detector (SPME-GC-ECD) method. Using this method, the plots of chlorinated pesticides concentrations and peak areas showed good linear correlation with R2 values in the range of 0.9887 to 0.9999. The percent recovery found at 1 μg L-1 and at 2 μg L- 1 concentration of pesticides ranged from 89.9 ± 3.9 % to 106.0 ± 2.3 and 88.5 ± 2.6 to 109.2 ± 2.9 %, respectively. The lower limits of detection for all 20 organochlorine pesticides were found significantly less than their maximum contamination levels. Among the various pesticides analyzed, β-BHC, γ-BHC, heptachlor, aldrin, α- chlordane, endosulfan I, 4,4''-DDE and dieldrin were detected in most of the water samples. However, other pesticides, like heptachlor epoxide, γ-chlordane, endrin, 4,4''-DDD, endrin ketone, 4,4''-DDT, methoxychlor, α-BHC, δ-BHC, endosulfan I, endosulfan II, endrin aldehyde and endosulfan sulfate were mostly present in only few water samples in the present investigation. Chlorpyrifos and monocrotophos are very toxic organophosphorous pesticides and have more importance due to their extensive use, large distribution and persistence in the environment. They are very dangerous by all routs of absorbtion, such as inhalation, ingestion and skin contact and producing various diseases. In the present study, the irradiation of chlorpyrifos and monocrotophos in aqueous solution by gamma-rays were investigated on a laboratory scale and their degradation efficiency was studied. The GC-ECD and HPLC (High performance liquid chromatography) were used for analysis of chlorpyrifos and monocrotophos, respectively. Aqueous solutions of different concentrations of chlorpyrifos compound (200–1000 μg L-1) were irradiated to different doses (30–575 Gy). Gamma irradiation showed 100 % degradation efficiency (η) for a 500 μg L-1 solution at an absorbed dose of 575 Gy. The dose rate of source was 300 Gy h -1. The radiolysis kinetics for decay of chlorpyrifos was pseudo-first order. The dose constants determined in this study ranged from 8.2 ´ 10-3 to 2.6 ´ 10-2 Gy−1, and decreased with an increase in the initial concentration of chlorpyrifos. The radiation chemical yield (G-values) for the loss of chlorpyrifos was found to decrease with increasing absorbed dose. The gamma radiation induced decomposition of monocrotophos aqueous solution at various concentrations (60-150 mg L-1) was carried out and its removal efficiency (η) was investigated. At 1200 Gy absorbed dose of gamma irradiation, monocrotophos solution (60 mg L-1) showed 100% degradation. The dose constants investigated in this study ranged from 1.4 ´ 10-3 to 3.0 ´ 10-3 Gy-1. The monocrotophos solution prepared in tap water showed lower degradation than that solution prepared in Milli Q water. The effect of radical scavengers, such as tert-butanol, iso-propanol, H2O2, CO3-2, HCO3-, humic acid, NO3- and NO2- as well as saturation of solutions by N2, N2O or air on the degradation of chlorpyrifos and monocrotophos were also studied. The results showed that the oxidative hydroxyl radical (•OH) was the most important in the degradation of chlorpyrifos and monocrotophos, while the reductive radicals, aqueous electron (e-aq) and hydrogen radical (H•) were of less relative importance for the degradation of these two pesticides. The inorganic by-products of chlorpyrifos (Cl -, SO 4-2 and PO4 -3) and monocrotophos (NO3-, NH4+ and PO4-3) were quantitatively determined by ion chromatography (IC). The organic intermediates of monocrotophos degradation were determined by HPLC/MS and UPLC/MS/MS. A detail mechanism pathway for degradation of monocrotophos by gamma irradiation has been proposed. Keywords: Organochlorine pesticides; Chlorpyrifos; Monocrotophos; Gamma irradiation; SPME-GC-ECD; Advanced oxidation technologies; Ion chromatography; Water decontamination; UPLC/MS/MS; Degradation mechanism.
محقق ِنعت: ڈاکٹر شہزاد احمد بہت خوش نصیب ہیں وہ لوگ جن کے شب و روز سید الانبیاء والمرسلین صلی اللہ علیہ و آلہٖ وسلم کی تعریف و توصیف کے بیان میں گزرتے ہیں۔ ایسے ہی خوش نصیب افراد میں ایک نام ڈاکٹر شہزاد احمد خان کا ہے۔ڈاکٹر صاحب کی نعت سے وابستگی نصف صدی پر محیط ہے۔جس پر بجا طور پر انھیں فخر بھی ہے ۔ شہزادؔ! میں بھی عاشقِ خیرالانام ہوں ہاتھوں میں میرے دیکھیے دامانِ نعت ہے فروغِ نعت کے حوالے سے ڈاکٹر صاحب کی خدمات کسی تعارف کی محتاج نہیں ہیں۔ آپ ۱۹۷۲ء سے ثناخوانی کررہے ہیں۔ مولانا اختر الحامدیؒ، علامہ سید محمد ہاشم فاضل شمسیؒ، مولانا عبدالقدوس قادریؒ، علامہ شمس بریلویؒ اور بابا سید رفیق عزیزی یوسفی تاجی ؒ جیسے بزرگوںکے آپ صحبت یافتہ ہیں۔ ایک اچھے نعت خواں اور نعت گو ہونے کے ساتھ ساتھ نعتیہ کتابوں کے مصنف و مرتب،تذکرہ نگار، نعتیہ رسائل کے مدیر، نعتیہ ادب کے محقق ، فروغِ نعت کے لیے قائم متعدد تنظیموں کے بانی اور نعتیہ کانفرنسوں اور جلسوں کے منتظم بھی ہیں۔ ڈاکٹر صاحب کا ایک بڑا کام ـ’’اردو نعت پاکستان میں‘‘ (نعتیہ شاعری کا تحقیقی جائزہ پاکستان کے خصوصی حوالے سے) کے عنوان سے وہ تحقیقی مقالہ ہے جس پر جامعہ کراچی نے انھیں پی ایچ۔ڈی۔ کی سند عطا کی ہے۔ اس سے نعتیہ ادب کے فروغ میں آپ کی محنت، تحقیق ، جستجو اور لگن کا اندازہ کیا جاسکتا ہے۔ عصر ِ حاضر میں نہ صرف حمدیہ و نعتیہ موضوعات پر ملکی و غیر ملکی جامعات میں ایم۔فل۔اور پی ایچ۔ڈی کی سطح پر تحقیقی مقالات لکھے جارہے ہیں بلکہ حمدو نعت سے وابستہ شخصیات بھی تحقیقی مقالات کا موضوع بن رہی ہیں۔ فروغِ نعت کے حوالے سے ڈاکٹر شہزاد صاحب کی خدمات یقینا اس لائق ہیں کہ انھیں...
This article delves into the fascinating intersection of art and science, exploring how artists have embraced the enigmatic world of quantum physics as a source of inspiration. It investigates the ways in which quantum theories, such as superposition and entanglement, have been translated into artistic expressions, challenging traditional boundaries between art and science. Through a multidisciplinary lens, this article examines the profound impact of quantum physics on the world of art and the complex interplay between abstract concepts and visual creativity.
In recent years, the Intelligent Transportation System (ITS) is gaining popularity for better road operations and convenience. One of the major application of ITS is integrating communication, control, computational, and sensing technologies deployed to improve road safety and efficiency, enhance mobility and reduce congestion. Vehicular communication technologies enable a decentralized network composed of moving vehicles which are equipped with wireless processing devices and Road Side Units (RSUs). Such networks allow vehicles for real-time exchange of traffic information with or without any support from fixed infrastructure. In vehicular ad hoc networks (VANETs), one major task is the distribution of safety alert messages generated by several interrelated applications. Safety applications are commonly linked to the hazardous circumstances that are accidents, traffic jams and pile ups. Thus, these applications require smaller data dissemination delay, vast coverage and unfailing delivery to all intended vehicles inside the vicinity. By considering the high speed of vehicles, VANETs present several unique challenges likely unbounded network size and topology, continual density variations, broadcast oriented communication, partitioned networks and intermittent connections among vehicles. This thesis emphasizes on the design and development of a data dissemination protocol to address the aforementioned challenges satisfying the provision of both highway and urban scenarios under varying traffic conditions. At first, this thesis provided a comprehensive comparative study of numerous multihop data dissemination protocols for VANETs. To achieve this objective, a large set of top quality references are considered which has been published during the preceding decade. Herein, a new scenario-driven taxonomy of data dissemination protocols is presented which assists the readers to review the interest of research community, advancement and innovation in the relevant technologies. After that an efficient and reliable data dissemination protocol is developed to improve the existing data ABSTRACT IX dissemination problems in VANETs working evenly in highway and urban scenarios under varying traffic densities. In this context, a store-carry-forward mechanism is employed to deal with disconnected sparse networks and a timer based broadcast suppression mechanism to mitigate the broadcast storm in dense networks. In addition, the proposed data dissemination solution is modified further to deal with scalability issues of vehicular networks. Thus, a Next Forwarding Vehicle (NFV) selection algorithm is used to select best vehicles as next forwarders of data packet inside vicinity. Afterward, this research addressed the challenging issue of data dissemination across network partitions. To overcome this issue, vehicles outside the Concerned Area (CA) are used for successful data delivery to all intended vehicles across the network partitions in urban scenarios. Finally, a mathematical model is developed for optimum NFV selection during data dissemination process. In this regard, Analytical Network Process (ANP) method is used to calculate the forwarding priorities of vehicles and selects the optimal NFV(s). To this end, criteria based on direction, position, and distance information of vehicles (with respect to the source vehicle) is set to compute the corresponding priorities of vehicles. The performance comparison was carried by simulation, using VEINS framework integrating the network simulator OMNET++ and mobility simulator SUMO. The simulation results revealed that the proposed work has improved the performance of data dissemination in VANETs against existing well-known data dissemination protocols. It performed better in terms of coverage by achieving approx. 100% delivery ratio in highway scenario. Even in partitioned urban scenario, it outperformed other evaluated protocols by 30 % more coverage. In addition, among the group of protocols that provide highest coverage, it showed reduced overhead by approximately 55%. In conclusion, the proposed protocol has significantly improved the data dissemination performance in terms of data packet delivery with acceptable minimum delay, reduced packet collisions and low overhead.