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S Joko J Numaga Y Fujino SM Islam K Masuda H Maeda 《Canadian Metallurgical Quarterly》1998,42(5):431-436
BACKGROUND: Neurenteric cysts are rare endothelium-lined structures. Two patients with symptomatic neurenteric cysts at the craniovertebral junction are presented. CASE PRESENTATION: Intermittent progression of neurologic symptoms delayed diagnosis for both patients. In one case, marked enlargement of the cyst was detected on serial imaging studies, and pathological examination of the excised lesion indicated rupture of the cyst. These cysts were totally resected by transoral or suboccipital approaches, as they were not firmly adherent to surrounding neural structures. The diagnosis of neurenteric cyst was confirmed by immunohistochemical analysis of the cyst wall. CONCLUSION: In view of the clinical course of these patients, we recommend early surgical resection of neurenteric cysts located at the craniovertebral junction. 相似文献
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Surface grafting of poly(pentafluorostyrene) on the iron and iron oxide particles via reversible addition fragmentation chain transfer (RAFT) polymerization 下载免费PDF全文
A surface grafting technique is reported for synthesis of poly(pentafluorostyrene) via reversible addition fragmentation chain transfer onto iron (iron oxide) particles. 4‐Methoxydithiobenzoate is used for the RAFT chain transfer agent. The molecular weight, surface morphology, thickness, thermal properties, and monomer conversion of the grafted polymer are reported. The grafted poly(pentafluorostyrene)–iron particles show a higher thermal transition temperature compared to the nongrafted polymer because it is speculated that the covalent bond between the polymer backbone and the surface of the iron particles restricts the molecular mobility. The monomer conversion increases in proportion to the amount of chain transfer agent (CTA) concentration at early polymerization time. The grafted poly(pentafluorostyrene) shows a “hairy” like polymer architecture with fibril thickness in the range of 80 to 100 nm. A thin coating is expected to maintain the magnetic saturation properties of iron particles. To the best of our knowledge, this is the first time that poly(pentafluorostyrene) has been grafted onto the iron particles utilizing RAFT and 4‐methoxydithiobenzoate as a CTA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44898. 相似文献
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Tri Joko Raharjo Yusrina Nabila Chairani Chudori Fransentino Wahyu Agustina 《Journal of Food Safety》2019,39(6)
We developed an assay for detecting pork adulteration in meat and meatballs using real‐time polymerase chain reaction involving specific primers and a TaqMan probe targeting the porcine mitochondrial (mt) ATPase 6 gene. We proved the specificity of the probe by showing no amplification from DNA isolated from six different meat‐providing species: cattle, dog, mouse, chicken, goat, and horse. On the contrary, DNA isolated from pork was positive for amplification, with a Ct (threshold cycle) of 18.69 using a standard amount of DNA template (50 ng). The presence of matrix and food processing steps in meatball sample had no influence on the specificity of the probe. The developed technique also has a good repeatability (CV, coefficient of variation = 3.86% for meat and 5.07% for meatballs), showing good linearity and sensitivity, with a limit of detection up to 5 pg of pork total DNA, which equivalent to approximately 6.8 copies of pork mtDNA. In addition, the analysis of spiked pork in beef meatballs showed that the method could determine up to 1% pork contamination. Moreover, the system was successfully applied to detect pork adulteration in commercial meatballs by detecting the presence of pork DNA in two samples. 相似文献
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A surface grafting technique for poly(2‐fluorostyrene) onto iron particles via atom transfer radical polymerization (ATRP) is described. Grafted poly(2‐fluorostyrene)–iron particles were synthesized by immobilizing 2‐4(‐chlorosulfonylphenyl)‐ethyltrichlorosilane to the iron particles through the covalent bond of a silanol group, followed by the polymerization of 2‐fluorostyrene monomer. The grafted polymer–iron particles display a higher thermal transition temperature compared to bulk polymer because the covalent bond between the polymer backbone and the surface of the iron particles restricts the molecular mobility. The molecular weight of the synthesized poly(2‐fluorostyrene) has been measured and it has a narrow molecular weight distribution (Mw/Mn < 1.1). From thermogravimetric analysis, the thermal stability of poly(2‐fluorostyrene) is superior to polystyrene. Also, the high viscosity magnetorheological fluid (HVMRF) prepared from surface coated iron particles has excellent thermo–oxidative stability, having nearly constant viscosity. These materials exhibit a large increase in shear yield stress for the off‐ and on‐state as compared to a benchmark high viscosity magnetorheological fluid (HVMRF) and ‐coated iron particle HVMRF. In addition, this type of fluid eliminates iron particle settling which is a common problem found in traditional magnetorheological fluids (MRFs). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
6.
Nughthoh Arfawi Kurdhi Joko Prasetyo Sri Sulistijowati Handajani 《International journal of systems science》2016,47(3):662-671
This paper presents and analyses the continuous review inventory model with order quantity, safety factor, back-order price discount, ordering cost and lead time as decision variables. Our work is based on the paper of Huang (2010). We extend the model to incorporate the situation when the amount received is uncertain. The lead time demand is assumed follows a normal distribution. A solution procedure is developed to find the optimal solution. A numerical example is given to illustrate the model. A sensitivity analysis is also included to describe the effects of changes in the model parameters on the expected annual cost. 相似文献
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St. Maryam Sismindari Tri Joko Raharjo Sudjadi Abdul Rohman 《International Journal of Food Properties》2016,19(1):187-195
The identifications of species in meat products have created interests since these foods became the target of forgery and fraud in the market. The presence of pork in food products is not allowed for the Muslim community. Hence, an analysis is necessary to detect the presence of pork in processed meat products, such as in dendeng (dried meat) product. Real time polymerase chain reaction using mitochondrial displacement loop686 and cytochrome b (cytb) gene primers was used to identify specific pork DNA among other four types of DNA species; namely beef, chicken, goat, and horse. This method was also used to identify pork DNA in the laboratory processed pork-beef dendeng as well as commercial dendeng from market. The results showed that real time polymerase chain reaction using displacement loop686 and cytb gene primers were able specifically to distinguish between pork DNA and the other species. The lowest concentration of 0.5% of pork DNA in a mixture of pork-beef processed products of dendeng was able to be detected by both primers with the product amplification of 114 and 134 bp (base pair) for the displacement loop686 and 149 bp for cytb gene, respectively. High sensitivity was also obtained when both primers were applied with the lowest detection limit of 5 pg/µL pork DNA. The results of the six commercial dendeng amplification using both primers showed no amplified products present, meaning that these products do not contain porcine DNA. 相似文献
8.
Joko Sulistyo Toshimitsu Hata Hiroyuki Kitagawa Paul Bronsveld Masashi Fujisawa Kozo Hashimoto Yuji Imamura 《Journal of Materials Science》2010,45(4):1107-1116
Porous SiC/SiO2/C composites exhibiting a wide range of high thermal and electrical conductivities were developed from carbonized wood infiltrated
with SiO2. As a pre-treatment, the samples were either heated at 100 °C or kept at room temperature followed by sintering in the temperature
range 1200–1800 °C. The microstructure, the morphology, and the electrical and thermal conductivities of the composites were
investigated. Pre-treatment at room temperature followed by sintering up to 1800 °C produced composites exhibiting a greater
size of carbon crystallites, a higher ordering of the microstructure of carbon and β-SiC and a smaller amount of SiO2, resulting in electrical and thermal conductivities of 1.17 × 104 Ω−1 m−1 and 25 W/mK, respectively. The thermal conductivity could be further improved to 101 W/mK by increasing the density of the
composite to 1.82 g/cm3. In contrast, the pre-treatment at 100 °C produced composites possessing a lower thermal conductivity of 2 W/mK. 相似文献
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The use of displacement threshold for switching frequency strategy for structural vibration mitigation 总被引:1,自引:0,他引:1
Joko Widjaja Bijan Samali Jianchun Li 《Journal of Mechanical Science and Technology》2007,21(6):865-869
This paper presents a study of controllable real-time frequency shift using a fluid pin damper, so called ‘smart pin’, mounted
at a beam-column connection. Unlike the stationary frequency shifter, the pin can increase or decrease the rotational stiffness
of the connection, leading to an actively adjustable structural frequency due to real-time responses of polarised magneto-rheological
(MR) fluid, whose rheological properties can change in milliseconds. The feedback to the pin damper governs the structural
frequency changes. To demonstrate this concept, a single storey plane steel frame model with one hinge and one ‘smart pin’
damper, mounted at each beam-column connection and subjected to two scaled earthquake excitations, namely El-Centro 1940 and
Northridge 1994, which respectively represent near- and farfield excitations, was tested using the shake table at the University
of Technology, Sydney (UTS) structures laboratory, for ‘proof-of-concept’ investigation. Further, the dynamic performance
of the model using a proposed switching strategy with a displacement threshold as an indicator for alternately supplied current
level (flip-flop) was examined, assuming the earthquake records were known. The results showed some potential use of this
control technique for structural vibration mitigation, however, further study to optimize the performance of the switching
strategy is still required.
An erratum to this article is available at . 相似文献