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101.
Fatma Cavus Yonar Gulten Rayimoglu Beril Anilanmert Emel Hulya Yukseloglu Salih Cengiz 《Electrophoresis》2022,43(3):425-436
The questions on which judges/prosecutors apply for expertise are mostly about by whom a document was drafted/signed. In this study, a new collective strategy was constructed including a collection method, a modified-silica-based DNA isolation method, and a novel purification method on four contact traces formed on four different paper surface during writing, using PCR with AmpFlSTR®GlobalFiler™ STR kit (after experimental comparison between three different kits) and identification using CE. This collective analysis approach is more sensitive and superior to its equivalents on questioned documents in literature because quantifiable amounts of touch DNA and profiles with high loci percentages (100% on day 1, 72.72% after 1 week) were obtained up to 1 week even after the most challenging conditions of sample forming that a forensic scientist can meet; as washing hands just before drafting and using a very low pressure in a shorter time (simulating a simple contact real conditions while drafting), using no visualizing technique that damages the document. Using the strategy, four most commonly used paper types were compared, to see in which of them DNA could be recovered better. The success of this strategy was shown on the 1-day to 10-year-old real samples from a diary and some archive documents from a law office (including the mix-DNA and different ballpoint pens). Thus, it became possible to show if a person had touched the document, in high success rates up to 1 week as a secondary evidence, when primary evidences are insufficient for the detection of document fraud offenses. 相似文献
102.
M. Cengiz Dökmeci 《Journal of Elasticity》1973,3(1):27-43
A detailed theoretical analysis of stress and strain in fiber-reinforced, laminated composite beams is presented within the framework of three-dimensional theory of thermo-elastodynamics. Each of reinforcing and matrix layers is made of different anisotropic material and is of different constant thickness. By the use of a variational theorem, the fully non-linear governing equations are consistently obtained for the case when the displacement components of each layer are taken to vary linearly over the cross-section of the layer. Then the linear version of the resulting equations, including the uniqueness of its solution is given, and the general results are briefly discussed.
Zusammenfassung In der vorliegenden Abhandlung wird eine detaillierte Spannungs-und Verzerrungsuntersuchung von faserverstärkten laminierten Balken innerhalb der dreidimensionalen thermo-elastodynamischen Theorie durchgeführt. Für jede Verstärkungs-und Bindeschicht wird unterschiedliches anisotropes Verhalten und unterschiedliche Schichtstärke vorausgesetzt. Unter Annahme eines linearen Verlaufs der im Querschnitt liegenden Verformungskomponenten über jede einzelne Schicht werden mit Hilfe eines Satzes der Variationsrechnung die vollständigen nichtlinearen Grundgleichungen abgeleitet. Damit ist auch die linearisierte Form der Gleichungen mit eindeutiger Lösung bestimmt. Eine kurze Untersuchung der Ergebnisse in ihrer allgemeinen Form ist angeschlossen.相似文献
103.
Summary A dynamical continuum theory is developed for laminated composite beams. Starting with an assumed displacement- and temperature field, the one-dimensional approximate theory is consistently constructed within the frame of the three-dimensional theory of linear, nonisothermal, anisotropic, coupled viscoelasticity. Each constituent of the beam may possess different constant thickness and mechanical properties. All dynamic interactions between the adjacent constituents are included. Further, the effects of transverse shear and normal strains and rotatory inertia as well as those of cross-sectional distortion are all taken into account. The resulting equations consist of the macroscopic beam equations of motion and heat conduction, the kinematical relations, the initial and boundary conditions and the constitutive equations, and they govern the extensional, flexural and torsional motions of laminated composite beams. The special cases of constituents which made of either isotropic thermoviscoelastic or anisotropic thermoelastic materials are discussed briefly.Supported by the Office of Naval Research.With 1 figure 相似文献
104.
Pharmacy staff and health care workers in hospitals may be exposed to antineoplastic drugs during cancer chemotherapy. Sensitive methods should be used to monitor the occupational exposure in biofluids such as urine. In this study, a sensitive method for cyclophosphamide determination in urine with high recovery was developed and validated for monitoring occupational exposure. Triple liquid-liquid extraction with ethyl acetate/dichloromethane (φr= 3:1; 6.0 mL) was applied. Good separation of cyclophosphamide and ifosfamide was achieved in a 9.0 min analysis, using liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). Limit of detection and limit of quantification were 0.07 ng mL?1 and 0.11 ng mL?1, respectively. Repeatability (RSD, %) was ≤ 12.74%. Inter-day and inter-analyst precision values (RSD, %) were ≤ 13.94% and 12.59%. Mean recovery for three different concentrations was (101.62 ± 6.05) %. The validation results were fitted for the purpose of routine monitoring of occupational cyclophosphamide exposure in hospital staff. 相似文献
105.
A novel, fast liquid chromatography atmospheric pressure chemical ionization mass spectrometry (LC–APCI–MS/MS) screening method was developed to determine the trace amounts of TNT (trinitrotoluene), RDX (1,3,5-trinitroperhydro-1,3,5-triazine), HMX (cyclotetramethylene-tetranitramine), PETN (pentaerythritoltetranitrate), TETRYL (2,4,6-trinitrophenyl-N-methylnitramine), picric acid (2,4,6 trinitrophenol), 2,6-DNT (2,6-dinitrotoluene), and TMETN (trimethylolethane-trinitrate) which contaminate the soil after explosion. A gradient of 2.00 mM ammonium nitrate aqueous solution-methanol mobile system, C18 column, and atmospheric pressure chemical ionization (APCI) (?) ionization mode was used after a single-step solid–liquid extraction procedure from soil matrix. Phenytoin was used as the internal standard. As an extraordinary application, gas temperature gradient in an APCI ionization was used. Analytes were selectively eluted from the system within 10 min. Average recovery obtained from the soil was between 93.01 and 104.20% at 250.0, 500.0, and 1000.0 ngg?1 concentration levels. Limit of detection (LOD) and limit of quantification (LOQ) values obtained from the analysis of the soil samples including explosive mix were between 8.9–161.2 and 13.2–241.5 ngg?1, respectively. 相似文献
106.
107.
Mustafa Samac evket Hakan Üngren Yunus Akamur Cengiz Arc Diner Ülkü 《Heteroatom Chemistry》2005,16(3):235-241
Furan‐3(2H)‐ones ( 3 ) were obtained from some 2,3‐dihydro‐furan‐2,3‐diones with a few Wittig reagents ( 2 ). The compounds of 3 with glycin and hydrazines ( 4a,b ) produced 2,3‐dihydro‐1H‐pyrrol‐3‐ones ( 5a–d ). All the reaction mechanisms were discussed by utilizing the similar reaction pathways. Structures of these compounds were determined by the IR, NMR, elemental analysis, and X‐ray diffraction method. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:235–241, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20115 相似文献
108.
In this study,the electronic transition properties and structural analysis of the metal complexes(Ni(Ⅱ),Co(Ⅱ),Cu(Ⅱ)and Mn(Ⅱ))of three different polymer ligands were performed by using XRF and X-ray diffraction(XRD)techniques,respectively.The structural analysis of the polymers and their complexes were performed by XRD technique and some of the polymers were found to be in the face-centred cubic(fcc)structure.In addition,the values of the present K X-ray intensity ratios are significantly greater than the values reported in literature. 相似文献
109.
The main purpose of this paper is to study some properties of integrable commutative hypercomplex structures endowed with a holomorphic torsion-free affine connection whose curvature tensor satisfies the purity condition with respect to the covariantly constant structure affinors. 相似文献
110.
Ozalp VC 《Analytical and bioanalytical chemistry》2012,402(2):799-804
An interferometry-based method was developed for detection of a small molecule, argininamide. The quantification of argininamide
was demonstrated using aptamers immobilized on silicone oxynitride sensor surface via avidin–biotin binding. The aptamers
formed a thin film over avidin layer corresponding to a thickness of 1.2 nm, consistent with a molecular positioning of multipoint
attachment to the surface. The binding of argininamide did not cause any significant changes in the thickness of the aptamer
film, suggesting that the specific binding did not affect the overall conformation of the aptamer molecules after adaptive
rearrangement of aptamer molecules. However, the binding results in clearly detectable changes in mass calculated from multiple
parameters determined by mass deposition and structural changes. The limit of detection of the developed sensor was determined
to be 5 μM. The sensor can monitor real-time changes in argininamide concentrations with high reliability and sensitivity.
The model system demonstrated that a combined measurement considering structural and mass changes through interferometry-based
techniques can overcome one of the major problems associated with real-time monitoring of small mass analytes. 相似文献