Earthquake response of nanocomposite concrete pipes conveying and immersing in fluid using numerical methods

Mostafa Maleki,Mahmood Rabani Bidgoli,Reza Kolahchi 사단법인 한국계산역학회 2019 Computers and Concrete, An International Journal Vol.24 No.2

Concrete pipelines are the most efficient and safe means for gas and oil transportation over a long distance. The use ofnano materials and nono-engineering can be considered for enhancing concrete pipelines properties. the tests show that SiO2 nanoparticles can improve the mechanical behavior of concrete.Moreover, severe hazard for pipelines is seismic ground motion. Over the years, scientists have attempted to understand pipe behavior against earthquake most frequently via numerical modeling and simulation. Therefore, in this paper, the dynamic response of underwater nanocomposite submerged pipeline conveying fluid is studied. The structure is subjected to the dynamic loads caused by earthquake and the governing equations of the system are derived using mathematical model via Classic shell theory and Hamilton's principle. Navier-Stokes equation is employed to calculate the force due to the fluid in the pipe. As well, the effect of external fluid is modeled with an external force. Mori-Tanaka approach is used to estimate the equivalent material properties of the nanocomposite. 1978 Tabas earthquake in Iran is considered for modelling seismic load.The dynamic displacement of the structure is extracted using differential quadrature method (DQM) and Newmark method.The effects of different parameters such asSiO2 nanoparticles volume percent,boundary conditions, thickness to radius ratios, length to radius ratios, internal and external fluidpressure and earthquake intensity are discussed on the seismic response of the structure.From results obtained in this paper, it can be found that the dynamic response of the pipe is increased in the presence of internal and external fluid. Furthermore, the use of SiO2 nanoparticles in concrete pipeline reduces the displacement of the structure during an earthquake.

Seismic response of underwater fluid-conveying concrete pipes reinforced with SiO2 nanoparticles using DQ and Newmark methods

Mostafa Maleki,Mahmood Rabani Bidgoli 사단법인 한국계산역학회 2018 Computers and Concrete, An International Journal Vol.21 No.6

Concrete pipelines are the most efficient and safe means for gas and oil transportation over a long distance. The use of nano materials and nono-engineering can be considered for enhancing concrete pipelines properties. the tests show that SiO2 nanoparticles can improve the mechanical behavior of concrete. Moreover, severe hazard for pipelines is seismic ground motion. Over the years, scientists have attempted to understand pipe behavior against earthquake most frequently via numerical modeling and simulation. Therefore, in this paper, the dynamic response of underwater nanocomposite submerged pipeline conveying fluid is studied. The structure is subjected to the dynamic loads caused by earthquake and the governing equations of the system are derived using mathematical model via Classic shell theory and Hamilton’s principle. Navier-Stokes equation is employed to calculate the force due to the fluid in the pipe. As well, the effect of external fluid is modeled with an external force. Mori-Tanaka approach is used to estimate the equivalent material properties of the nanocomposite. 1978 Tabas earthquake in Iran is considered for modelling seismic load. The dynamic displacement of the structure is extracted using differential quadrature method (DQM) and Newmark method. The effects of different parameters such as SiO2 nanoparticles volume percent, boundary conditions, thickness to radius ratios, length to radius ratios, internal and external fluid pressure and earthquake intensity are discussed on the seismic response of the structure. From results obtained in this paper, it can be found that the dynamic response of the pipe is increased in the presence of internal and external fluid. Furthermore, the use of SiO2 nanoparticles in concrete pipeline reduces the displacement of the structure during an earthquake.

Epidemiology of Oral Cancer in Iran: a Systematic Review

Maleki, Davood,Ghojazadeh, Morteza,Mahmoudi, Seyed-Sajjad,Mahmoudi, Seed-Mostafa,Pournaghi-Azar, Fatemeh,Torab, Ali,Piri, Reza,Azami-Aghdash, Saber,Naghavi-Behzad, Mohammad Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.13

Background: Oral cancer stands among the 10 top causes of cancer death in the world. Considering the role of epidemiologic information on planning and effective interventions, the present study aimed to investigate the epidemiology of oral cancer in Iran. Materials and Methods: The required information for this systematic review study was obtained from PubMed, Google Scholar, CINAHL,SID, Medlib, Magiran and Iranmedex databases, using key words "cancer", "oral cancer", "squamous cell carcinoma", "oral cavity carcinoma" and their Persian equivalents in combination with keywords of epidemiology, prevalence, etiology, frequency, and Iran from 1990 to 2014. From 1,065 related studies found, finally 25 were included to the study. Results: The mean age of 8,248 patients in 25 studies was $54.0{\pm}15.1years$. The male/female ratio for oral cancer was 1.91. Tongue with average percentage of 29.9 was the most involved site. Regarding microscopic grade, 65.7% of cases were grade 1. SCCs, accounting for an average of 70.0%, was the most common among all types of oral cancer. In the majority of studies, smoking including cigarette, hookah, and tobacco consumption was found to be a risk factor. Conclusions: The epidemiological pattern of oral cancer in Iran is somewhat similar to that of other countries. Yet the information on hand in this field is limited and considering the role of epidemiological data we suggest conducting more accurate studies to catch data that is required for effective programs and interventions.

1,3,5-Trichloro-2,4,6-Triazinetrion: A Versatile Heterocycle for the One-Pot Synthesis of 14-Aryl- or Alkyl -14H-Dibenzo[a,j]xanthene, 1,8-Dioxooctahydroxanthene and 12-Aryl-8,9,10,12-Tetrahydrobenzo[a]xanthene-11-one Derivatives under Solvent-Free Condi

Maleki, Behrooz,Gholizadeh, Mostafa,Sepehr, Zeinalabedin Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.5

A facile, green, efficient and environment-friendly protocol for the synthesis of 14-aryl- or alkyl-14Hdibenzo[a,j]xanthene, 1,8-dioxooctahydroxanthene and 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one have been developed by one-pot condensation of various aldehydes with (i) ${\beta}$-naphthol (ii) cyclic 1,3-dicarbonyl compounds and (iii) ${\beta}$-naphthol and cyclic 1,3-dicarbonyl compounds, in the presence of 1,3,5-trichloro-2,4,6-triazinetrion (trichloroisocyanuric acid, TCCA) as catalyst under solvent-free conditions. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, easy purification, and economic availability of the catalyst.

1,3,5-Trichloro-2,4,6-Triazinetrion: A Versatile Heterocycle for the One-Pot Synthesis of 14-Aryl- or Alkyl -14H-Dibenzo[a,j]xanthene, 1,8-Dioxooctahydroxanthene and 12-Aryl-8,9,10,12-Tetrahydrobenzo[a]xanthene-11-one Derivatives under Solvent-Free Condi

Behrooz Maleki,Mostafa Gholizadeh,Zeinalabedin Sepehr 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.5

A facile, green, efficient and environment-friendly protocol for the synthesis of 14-aryl- or alkyl-14Hdibenzo[a,j]xanthene, 1,8-dioxooctahydroxanthene and 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one have been developed by one-pot condensation of various aldehydes with (i) β-naphthol (ii) cyclic 1,3-dicarbonyl compounds and (iii) β-naphthol and cyclic 1,3-dicarbonyl compounds, in the presence of 1,3,5-trichloro-2,4,6-triazinetrion (trichloroisocyanuric acid, TCCA) as catalyst under solvent-free conditions. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, easy purification, and economic availability of the catalyst.

The efficacy of GABAergic precursor cells transplantation in alleviating neuropathic pain in animal models: a systematic review and meta-analysis

Shaghayegh Askarian-Amiri,Solmaz Nasseri Maleki,Seyedeh Niloufar Rafiei Alavi,Arian Madani Neishaboori,Amirmohammad Toloui,Mohammed I. M. Gubari,Arash Sarveazad,Mostafa Hosseini,Mahmoud Yousefifard 대한통증학회 2022 The Korean Journal of Pain Vol.35 No.1

Background: Current therapies are quite unsuccessful in the management of neuropathic pain. Therefore, considering the inhibitory characteristics of GABA mediators, the present systematic review and meta-analysis aimed to determine the efficacy of GABAergic neural precursor cells on neuropathic pain management. Methods: Search was conducted on Medline, Embase, Scopus, and Web of Science databases. A search strategy was designed based on the keywords related to GABAergic cells combined with neuropathic pain. The outcomes were allodynia and hyperalgesia. The results were reported as a pooled standardized mean difference (SMD) with a 95% confidence interval (95% CI). Results: Data of 13 studies were analyzed in the present meta-analysis. The results showed that administration of GABAergic cells improved allodynia (SMD = 1.79; 95% CI: 0.87, 271; P < 0.001) and hyperalgesia (SMD = 1.29; 95% CI: 0.26, 2.32; P = 0.019). Moreover, the analyses demonstrated that the efficacy of GABAergic cells in the management of allodynia and hyperalgesia is only observed in rats. Also, only genetically modified cells are effective in improving both of allodynia, and hyperalgesia. Conclusions: A moderate level of pre-clinical evidence showed that transplantation of genetically-modified GABAergic cells is effective in the management of neuropathic pain. However, it seems that the transplantation efficacy of these cells is only statistically significant in improving pain symptoms in rats. Hence, caution should be exercised regarding the generalizability and the translation of the findings from rats and mice studies to large animal studies and clinical trials.