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1.
Parisa Ghaemi Kaveh Shahabi John P. Wilson Farnoush Banaei-Kashani 《GeoInformatica》2014,18(2):229-251
Given a set S of sites and a set O of weighted objects, an optimal location query finds the location(s) where introducing a new site maximizes the total weight of the objects that are closer to the new site than to any other site. With such a query, for instance, a franchise corporation (e.g., McDonald’s) can find a location to open a new store such that the number of potential store customers (i.e., people living close to the store) is maximized. Optimal location queries are computationally complex to compute and require efficient solutions that scale with large datasets. Previously, two specific approaches have been proposed for efficient computation of optimal location queries. However, they both assume p-norm distance (namely, L1 and L2/Euclidean); hence, they are not applicable where sites and objects are located on spatial networks. In this article, we focus on optimal network location (ONL) queries, i.e., optimal location queries in which objects and sites reside on a spatial network. We introduce two complementary approaches, namely EONL (short for Expansion-based ONL) and BONL (short for Bound-based ONL), which enable efficient computation of ONL queries with datasets of uniform and skewed distributions, respectively. Moreover, with an extensive experimental study we verify and compare the efficiency of our proposed approaches with real world datasets, and we demonstrate the importance of considering network distance (rather than p-norm distance) with ONL queries. 相似文献
2.
Hassan Ali Zamani Alihossien ImaniAli Arvinfar Fatemeh RahimiMohammad Reza Ganjali Farnoush FaridbodSoraia Meghdadi 《Materials science & engineering. C, Materials for biological applications》2011,31(3):588-592
A new selective Nd(III) sensor has been made by using N,N′-bis(quinoline-2-carboxamido)-4,5-dimethylbenzene (H2L4) as a suitable ionophore. The sensor exhibits Nernstian response to Nd(III) ions in the concentration range of 5.0 × 10− 6 to 1.0 × 10− 2 M. It displays a Nernstian slope of 19.5 ± 0.4 mV/decade in the pH range of 2.9-9.2. The proposed sensor also exhibits a fast response time of < l0 s. The detection limit of the proposed sensor is 4.8 × 10− 6 M, and it can be used over a period of 10 weeks without significant changes in its response. Furthermore, the electrode showed high selectivity toward Nd(III) ion respect to all other lanthanide ions tested. The practical utility of the sensor was demonstrated by using it as an indicator electrode in the potentiometric determination of Nd(III) ions in certified reference material and spiked water samples. 相似文献
3.
M. R. Ganjali P. Norouzi F. Faridbod S. Riahi M. R. Yaftian A. Zamani D. Matt 《Journal of Applied Electrochemistry》2007,37(7):827-833
A Th4+ ion-selective membrane sensor was fabricated from poly (vinyl chloride) (PVC) matrix membrane containing 2-(diphenylphosphorothioyl)-N′,N′-diphenyl acetamide (DPTD) as a neutral carrier, potassium tetrakis (p-chlorophenyl) borate (KTpClPB) as anionic excluder and o-nitrophenyloctyl ether (NPOE) as a plasticizing solvent mediator. The effects of the membrane composition, pH and additive
anionic influence on the response properties were investigated. The sensor, comprising 30% PVC, 63% solvent mediator, 4% ionophore
and 3% anionic additive demonstrates the best potentiometric response characteristics. It displays Nernstian behavior (15.2 ± 0.5 mV
per decade) over the concentration range 1.0 × 10−2–1.0 × 10−6 M. The detection limit of the electrode is 6.3 × 10−7 M (∼140 ng/ml). The response time of the electrode is 30 s .The sensor can be used in the pH range 3.0–9.0 for about 6 weeks.
The membrane sensor was used as an indicator electrode in the potentiometric titration of Th4+ ions with EDTA. It was successfully applied to the determination of thorium ions in binary mixture. 相似文献
4.
Farnoush Faridbod Mohammad Reza Ganjali Bagher Larijani Parviz Norouzi 《Electrochimica acta》2009,55(1):234-239
Solution studies showed the strong interaction of [5-(dimethylamino) naphthalene-1-sulfonyl 4-phenylsemicarbazide] (NSP) with Er(III) ions. NSP was used as a sensing material during construction of carbon paste Er(III) sensors. The electrodes were modified with 1-n-butyl-3-methylimidazolium tetrafluoroborate, [bmim]BF4, as room temperature ionic liquid (RTIL) and multi-walled carbon nanotube (MWCNT). Potentiometric sensors constructed with [bmim]BF4 and MWCNTs show better sensitivity, selectivity, response time, and response stability compared to Er(III) carbon paste sensors. The best performance for the modified sensor was obtained with an electrode composition of 20% [bmim]BF4, 20% NSP, 45% graphite powder and 15% MWCNT. This particular sensor formulation exhibits a Nernstian response (19.8 ± 0.3 mV decade−1) toward Er(III) ions in the range of 1.0 × 10−7 to 1.0 × 10−1 mol L−1 with a detection limit of 5.0 × 10−8 mol L−1. The proposed modified Er(III) sensor can be used over the pH range from 3.5 to 9.0. 相似文献
5.
M.R. Ganjali M. Hosseini A. Ghafarloo M. Khoobi F. Faridbod A. Shafiee P. Norouzi 《Materials science & engineering. C, Materials for biological applications》2013,33(7):4140-4143
(E)-2-(1-(4-hydroxy-2-oxo-2H-chromen-3-yl)ethylidene)hydrazinecarbothioamide (L) has been used to detect trace amounts of praseodymium ion in acetonitrile–water solution (MeCN/H2O) by fluorescence spectroscopy. The fluorescent probe undergoes fluorescent emission intensity enhancement upon binding to Pr3 + ions in MeCN/H2O (9/1:v/v) solution. The fluorescence enhancement of L is attributed to a 1:1 complex formation between L and Pr3 +, which has been utilized as the basis for selective detection of Pr3 +. The sensor can be applied to the quantification of praseodymium ion with a linear range of 1.6 × 10? 7 to 1.0 × 10? 5 M. The limit of detection was 8.3 × 10? 8 M. The sensor exhibits high selectivity toward praseodymium ions in comparison with common metal ions. The proposed fluorescent sensor was successfully used for determination of Pr3 + in water samples. 相似文献
6.
Hassan Ali Zamani Mohammad Saleh Zabihi Mitra Rohani Abbas Zangeneh-Asadabadi Mohammad Reza Ganjali Farnoush Faridbod Soraia Meghdadi 《Materials science & engineering. C, Materials for biological applications》2011,31(2):409-413
Solution study showed N,N′-bis(5-nitrosalicylidene)-2-aminobenzylamin (L) trends toward Tb3+ ion. Then, it was used as a suitable ionophore in construction of terbium ion selective electrode. The electrode with composition of 30% PVC, 65% solvent mediator (NB), 3% ionophore (L) and 2% anionic additive (NaTPB) shows the best potentiometric response characteristics. It displays a Nernstian behavior (20.1 mV decade?1) over the concentration range 1.0 × 10? 6 to 1.0 × 10? 2 mol L?1. The detection limit of the electrode is 6.3 × 10? 7 mol L?1. It has a very short response time (~ 10 s) and a useful working pH range of 2.6–9.4 for at least 2 months. The proposed membrane sensor shows excellent discriminating ability towards Tb3+ ions with regard to several alkali, alkaline earth, transition and heavy metal ions. To investigate the analytical applicability of the sensor, it was successfully applied to the determination of terbium in certified reference material. 相似文献
7.
Mohammad Reza Ganjali Parviz Norouzi Alireza Atrian Farnoush Faridbod Soraia Meghdadi Masoud Giahi 《Materials science & engineering. C, Materials for biological applications》2009,29(1):205-210
The biological properties of the lutetium as well as other lanthanide ions, primarily based on their similarity to calcium, have been the bases for research into potential therapeutic applications of lanthanide series since the early part of the twentieth century. In this research, a Lu(III) potentiometric membrane sensor based on N,N′-bis(2-pyridinecarboxamide)-1,2-ethane (PCAE) is described. The sensor exhibits a Nernstian response over a concentration range of 1.0 × 10? 6 mol L? 1–1.0 × 10? 1 mol L? 1, with a detection limit of 6.0 × 10? 7 mol L? 1. The best performance was achieved with a membrane composition, consisting of 30% PVC, 63% o-nitrophenyl octyl ether (NPOE), 5% PCAE and 2% sodium tetraphenylborate (NaTPB). It was found that at the pH range of 4.0–9.0, the potential response of the sensor was not affected by the pH. Furthermore, the electrode presents satisfactory reproducibility, very fast response time (5 s) and relatively good discriminating ability for Lu(III) ions with respect to many common cations and other lanthanide ions. The sensor has been applied to the determination of Lu(III) in human serum and in some soil samples where domestic devices were stored. 相似文献
8.
Hamid Ezzatpanah Vicente M. Gómez-López Tatiana Koutchma Farnoush Lavafpour Frank Moerman Mohammad Mohammadi Dele Raheem 《Comprehensive Reviews in Food Science and Food Safety》2022,21(2):904-941
Food- and waterborne viruses, such as human norovirus, hepatitis A virus, hepatitis E virus, rotaviruses, astroviruses, adenoviruses, and enteroviruses, are major contributors to all foodborne illnesses. Their small size, structure, and ability to clump and attach to inanimate surfaces make viruses challenging to reduce or eliminate, especially in the presence of inorganic or organic soils. Besides traditional wet and dry methods of disinfection using chemicals and heat, emerging physical nonthermal decontamination techniques (irradiation, ultraviolet, pulsed light, high hydrostatic pressure, cold atmospheric plasma, and pulsed electric field), novel virucidal surfaces, and bioactive compounds are examined for their potential to inactivate viruses on the surfaces of foods or food contact surfaces (tools, equipment, hands, etc.). Every disinfection technique is discussed based on its efficiency against viruses, specific advantages and disadvantages, and limitations. Structure, genomic organization, and molecular biology of different virus strains are reviewed, as they are key in determining these techniques effectiveness in controlling all or specific foodborne viruses. Selecting suitable viral decontamination techniques requires that their antiviral mechanism of action and ability to reduce virus infectivity must be taken into consideration. Furthermore, details about critical treatments parameters essential to control foodborne viruses in a food production environment are discussed, as they are also determinative in defining best disinfection and hygiene practices preventing viral infection after consuming a food product. 相似文献
9.
Mohammad Reza Parviz Farnoush Mohammad Leila Masoud 《Sensors and actuators. B, Chemical》2007,120(2):494-499
The perchlorate salts of nickel(II) complexes of 1,3,5,8,10,13-hexaazacyclotetradecane (1) and 1,8-tert-butyl-1,3,5,8,10,13-hexaazacyclotetradecane (2) were used in construction of PVC based membrane electrodes. These sensors show very good selectivity for ClO4− ions over a wide variety of anions. These electrodes exhibit Nernstian behavior with the slopes of 59.5 and 59.3 mV per decade for (1) and (2), respectively. The working concentration ranges of the sensors are 1.0 × 10−1–9.0 × 10−7 M (1) and 1.0 × 10−1–5.0 × 10−7 M (2) with the detection limits of 6.0 × 10−7 and 2.0 × 10−7 M, respectively. The response time of the both sensors is very fast, and can be used for 2 (I) and 12 (II) weeks in a pH range of 3.0–11.0. These electrodes were applied to the determination of perchlorate ions in wastewater and cattle urine samples. 相似文献
10.
Hassan Ali Zamani Rahman KamjooMajid Mohammadhosseini Mojdeh ZaferoniZynab Rafati Mohammad Reza Ganjali Farnoush FaridbodSoraia Meghdadi 《Materials science & engineering. C, Materials for biological applications》2012,32(3):447-451
Conductometric study in acetonitrile solution shows the selectivity of PCQ toward europium ion. Therefore, a new europium PVC membrane electrode was prepared based on N-pyridine-2-carboxamido-8-aminoquinoline (PCQ) as an ion carrier. The electrode has a wide concentration range from 1.0 × 10− 2 and 1.0 × 10− 6 mol L− 1, Nernstian slope of 19.8 ± 0.3 mV per decade and a detection limit of 6.4 × 10− 7 mol L− 1. The potentiometric response is pH independent in the range of 2.4-7.4. The proposed sensor has a relatively fast response time less than 10 s and it can be used for at least 2 months without any considerable divergence in its potentials. The proposed electrode revealed good selectivity toward europium ion in comparison with variety of other metal ions. The practical utility of the electrodes has been demonstrated by their use as indicator electrodes in the potentiometric titration of Eu3 + ions with EDTA and for determination of Eu3 + ion concentration in mixtures of two and three different ions. 相似文献