bluuebunny/crossref_metadata_2025 huggingface dataset:
Testing and analysis of a traditional oak frame
Authors: Hill T. , Shanks J. , Stott J. , Walker P.
Published: January 2007

Despite the widespread historical use of green oak framing, using all-timber connections, their engineering performance is poorly understood. Restoration of existing structures and design of new buildings are both often reliant on the skills of the carpenter and historical precedents. Structural engineers frequently struggle to validate green oak frame designs using modern codes of practice. The present paper presents findings from a study undertaken to investigate the structural performance of arched-braced green oak sub-frames. The sub-frames were part of a traditional roof structure in a barn that had fallen into disrepair and was to be replaced. To inform the design process and improve engineering understanding, five identical arched-braced sub-frames were commissioned for load testing under laboratory conditions to failure. The experimental results from the sub-frame tests, including deformation and load capacity, are presented. Experimental load capacities are compared with a novel collapse load analysis.
The double-curvature masonry vaults of Eladio Dieste
Authors: Pedreschi R. , Theodossopoulos D.
Published: January 2007

The Uruguayan engineer Eladio Dieste developed an innovative construction method for wide-span roof structures. Known as Gaussian vaults, their double-curved geometry is based on the catenary resulting in mainly axial compressive forces. Whereas most thin wide-span roofs have been built using concrete, Dieste used brick, and unlike traditional masonry vaults, they are only one brick-layer in thickness. Typically the vaults have a low rise, the span-to-rise ratio is normally 8–10 and buckling is the likely mode of failure. Dieste used the curved surface of the vaults to resist buckling and developed design procedures to ensure their safety. In the present paper a brief background to Dieste's work is presented including his methods of analysis and the application is considered with reference to one of his larger projects, the warehouse at the docks in Montevideo, with a span of 45 m. Through an iterative mathematical procedure, Dieste formulated the critical loads of catenary arches into graphs. The method is compared with a finite-element study, which also considers the elastic deformations under self-weight, asymmetric loading owing to wind and ultimate failure owing to buckling.
Strut–tie analysis of beams with external tendons
Authors: El-Ariss B.
Published: January 2007

Strengthening of concrete beams by means of external tendons has been increasingly used. Analysis of such beams is more difficult than that of beams with internal bonded tendons because the stress in external tendons depends on the deformations of the whole beam. In the current paper, a simple model based on the strut-and-tie method is presented to predict the capacity of simply supported externally prestressed concrete beams subjected to equal concentrated loads at third-points. The model defines the struts and ties that form a load transfer mechanism in the beams. It predicts the ultimate loads the beam can carry and the force in the tendons at failure using the section method and equilibrium equations. When comparing the results obtained using the proposed model with others in the literature, the model was found to be conservative. The proposed model is intended to help designers in the inspection and structural assessment of beams.
Analysis of bending tests on CFRP-stiffened pultruded GRP beams
Authors: Turvey G. J.
Published: January 2007

The equations for the mid-span deflection and end rotations of carbon fibre reinforced plastic (CFRP) stiffened pultruded glass reinforced plastic (GRP) shear deformable beams with semi-rigid end connections are introduced. Two series of three-point flexure tests on simply supported pultruded GRP beams are described. In the first series the beams were tested in the unstiffened state and in the second series the beams were tested with pairs of CFRP strips of varying length bonded to their soffits. A third series of three-point flexure tests on a similar pultruded beam with the CFRP strips bonded over the whole span and with bolted stainless steel and GRP cleat end connections is also described. The shear deformable semi-rigid beam equations are used to predict the loads, deflections, end rotations and surface strains recorded in the three test series. It is shown that the correlation between the measured deflections, rotations and strains is generally good, given the nature of uncertainty surrounding some of the material properties. For example, the largest percentage difference between measured and predicted deflections was about 6% for the first two test series and 12% for the third series. It is concluded that this level of correlation between actual and predicted deformations vindicates the use of refined beam analysis for the more efficient design of CFRP stiffened pultruded GRP beams with practical end connections.
Expression of Variability in Corn as Influenced by Growth Stage Using Optical Sensor Measurements
Authors: Martin K. L. , Girma K. , Freeman K. W. , Teal R. K. , Tubańa B. , Arnall D. B. , Chung B. , Walsh O. , Solie J. B. , Stone M. L. , Raun W. R.
Published: February 2007

Improving crop management inputs with remote sensing devices is an emerging technology. This study documented the progression of the normalized difference vegetative index (NDVI) during the life cycle of corn (Zea mays L.), evaluated the spatial variability of corn growth in terms of the CV (calculated from NDVI readings), and documented the relationships between NDVI, CV (calculated from NDVI), and grain and biomass yields and plant density. Four rows, 30 m in length, from two locations during 2 yr were randomly selected for this study. An optical sensor was used to collect NDVI readings at multiple growth stages during the life cycle of corn. The NDVI increased with progression of vegetative growth stages until V10, where a plateau was encountered, followed by a decline in NDVI after the VT growth stage. Coefficient of variation data from the NDVI readings revealed two dominant peaks during the life cycle of corn, one between the V6 and V8 growth stages and the second during the late reproductive growth stages. The CV data illustrated that the greatest variation expressed by corn during the vegetative growth stages was between the V6 and V8 growth stages. The highest correlation of NDVI with corn grain yield was found at the V7 to V9 growth stages; likewise, CV and plant density were also more highly correlated from V7 to V9. The CV from NDVI readings was highly correlated with grain and biomass yields at all growth stages.
Wheezing and lung function measured in subjects exposed to various levels of fine particles and polycyclic aromatic hydrocarbons
Authors: Jedrychowski Wieslaw , Perera Frederica , Whyatt Robin , Mroz Elzbieta , Flak Elzbieta , Jacek Ryszard , Penar Agnieszka , Spengler John , Camman David
Published: January 2007

The main purpose of the study was to assess the occurrence of wheezing and lung function in non-smoking women exposed to various levels of fine particulate matter(FP) and polycyclic aromatic hydrocarbons (PAH). Out of the total study group, 152 women were included in the lower exposed group (PM2.5 ≤34.3μg/m3 or PAHs ≤ 22.9ng/ m3) and 96 persons in higher concentrations of both air pollutants (PM2.5>34.3μg/m3 and PAHs > 22.9ng/ m3). Except for FVC and FEV1, all lung forced ventilatory flows (PEFR, FEF25% FEF50%, FEF75%, FEF25−75%) were significantly lower in the higher exposed group. The findings suggest bronchoconstriction within the respiratory tract, which may be related to the exposure under study. This was consistent with a higher prevalence of wheezing in more exposed subjects. It was shown that higher levels of both pollutants increased the risk of wheezing by factor 5.6 (95% CI: 1.77–17.8) after accounting for potential confounders such as allergic diseases and exposure to ETS. This study suggests that pollutants in question may have the capacity to promote broncho-constriction and asthmatic symptoms, possibly by bronchial inflammation resulting from the exposure.
Clinical analysis of first-ever acute ischemic stroke involving the territory of paramedian mesencephalic arteries
Authors: Thajeb Peterus , Thajeb Teguh , Dai Dao-Fu
Published: January 2007

To determine one-year clinical outcome of patients with first-ever acute ischemic stroke involving the territory of paramedian mesencephalic arteries (PMAS), we conducted a prospective study evaluating the cognitive functions of 28 patients with PMAS. Neuropsychological tests were performed during the first month of stroke onset and at the 12th month of follow-up. There were 12 women and 16 men. Mean age of onset for women and men was 70 years and 65 years, respectively. Progressing strokes occurred in 62% of patients and 96% developed a full-blown picture of the clinical triad of akinetic mutism, hypersomnolence, and bilateral blepharoptosis and ophthalmoparesis. Involuntary movements occurred in 6, and focal myoclonus in 4 patients. The top four associated risk factors were hypertension (68%), hyperlipidemia (57%), diabetes mellitus (46%), and atrial fibrillation (36%). Unilateral midbrain infarctions occurred in 12 patients and bilateral lesions in 16. Thalamic infarctions were unilateral in 10 and bilateral in 13 cases. Three of the 28 (11%) patients died of recurrent cerebral infarctions within 1 year of the onset of PMAS. The recurrent infarctions involved the basilar artery territory in two cases and the carotid system in another. One patient died of acute myocardial infarction. Of the 24 patients who had survived the stroke by 1 year, 20 (71%) developed dementia. We conclude that first-ever ischemic stroke with PMAS is not a benign syndrome. Most patients developed dementia by 1 year after the stroke.
Meningococcal meningitis with myelopathy: case report and review of literature
Authors: Choudhary Nikhil , Kumar Nirmal , Ahlawat Ravinder , Jain Kapil , Rizvi Yasir , Agarwal Gaurav , Kaul Bhavna
Published: January 2007

Neisseria meningitis is a common etiological agent in bacterial meningitis in humans. Common complications associated with meningococcal meningitis include cranial nerve palsies, hydrocephalus, seizures, stroke, cerebritis or brain abscesses. Spinal cord dysfunction is a very rare complication of meningococcal meningitis and its occurrence is limited to case reports only. We report such a case along with a review of available literature and underlying pathogenetic mechanisms. Case report: Our patient diagnosed as a case of meningococcal meningitis developed multiple cranial nerve palsies followed by flaccid paraplegia with bowel bladder involvement during the recovery phase of the disease. Spine MRI showed mild cord edema and diffuse patchy areas of altered intramedullary signal intensity in dorsal cord suggestive of myelitis. The patient was treated with antibiotics and intravenous methyl-prednisolone along with supportive physiotherapy. His neurological deficits showed marked improvement on subsequent follow up.
Transient electrocardiographic recording of acute myocardial ischemia with ST-segment elevation of the diaphragmal location accompanied by a total atrioventricular block as an initial manifestation of Prinzmetal’s angina — A case report
Authors: Fuckar Krunoslav , Lakusic Nenad , Stipic Hrvoje
Published: January 2007

Prinzmetal’s angina, also known as Prinzmetal’s variant or Prinzmetal’s vasospastic angina is characterized by angina attacks caused by spasm of the great epicardial coronary arteries. Coronary artery endothelial dysfunction plays a crucial role in the development of this vasospastic angina. The attacks of vasospastic angina can be prevented with calcium antagonists and nitrates, whereas in refractory variant angina, coronary angioplasty with stenting may help prevent further coronary spasm. In this case report, we present a 52-year-old male patient with a transient electrocardiographic recording of acute myocardial ischemia with ST-segment elevation of the diaphragmal location accompanied by a total atrioventricular block immediately after exercise testing and as a first manifestation of Prinzmetal’s angina. After regression of the symptoms and electrocardiographic changes, significant pathomorphologic changes of coronary arteries were excluded by coronary angiography. Following discharge, the patient was treated with calcium antagonists and did not show symptoms during a 4-year follow-up period.
Anti-staphylococcal potential of Callistemon rigidus
Authors: Gomber Charu , Saxena Sanjai
Published: January 2007

The last decade witnessed the emergence of Staphylococcus aureus- a versatile human pathogen, as a deadly superbug. The enormous genetic plasticity of the organism assists it to endlessly evolve resistance mechanisms against existing anti-infectives thus necessitating the need to control the spread of resistant staphylococcal isolates in hospitals and health care settings. This in turn demands the incessant exploration of newer biological matrices in search of diverse chemical entities with novel drug targets. Since time immemorial higher plants continue to be the best source of newer compounds with high therapeutic potential. Lead fractions from same or different plants can be developed into effective antibacterial polyherbal formulations. A lead fraction from methanolic extract of leaves of Callistemon rigidus exhibited a dose dependent antistaphylococcal activity during in vitro agar well assay against a panel of twenty seven clinical multidrug resistant S. aureus isolates. Further, minimal inhibitory concentration (MIC) evaluation by in vitro 96-well microplate based assay established a MIC range of 1.25–80 μg/ml as compared to 5–320 μg/ml of positive control, Cefuroxime sodium. The MIC50 and MIC90 of the methanolic lead fraction were 5 μg/ml and 40 μg/ml respectively. The present study thus signifies the vast potential of the lead fraction from Callistemon rigidus for future development into a herbal drug/ formulation and to impede global health crisis due to multidrug resistant Staphylococcus aureus.
Management patterns of thrombosis prophylaxis and related costs in hip and knee replacement in Germany
Authors: McBride Doreen , Brüggenjürgen Bernd , Roll Stephanie , Quante Markus , Willich Stefan
Published: January 2007

The objective of the study was to depict treatment strategies, health care utilisation and cost evaluation of hip and knee replacement surgery in Germany, with a particular emphasis on thrombosis prophylaxis (TP) for the prevention of deep vein thrombosis (DVT). In this multi-centre prospective cohort study, medical record data (socio-demographics, risk factors for thrombosis, thrombosis prophylaxis, course of hospital stay) were collected for patients undergoing either total hip replacement (THR) or total knee replacement (TKR). One and three months post-operatively, post-operative outcomes and health care resource use were documented by patient and physician questionnaires. A total of 309 patients participated in the study (59% female, mean age 66 [SD 10] years). Parenteral anticoagulation was administered for a mean of 38 (SD 16) days. 27 (9%) patients received subsequent oral anticoagulation for a mean of 38 (SD 21) additional days. Symptomatic DVT was reported by four (1.3%) patients. Mean overall direct costs associated with surgery from baseline to 3 months were EUR 11 264 (median 11 564, SD 2 481). Hospital and rehabilitation accounted for 97% of direct costs; costs for medications, physical therapy, physician office visits, out-of-pocket expenses, as well as complication costs accounted for an additional 3% of direct costs. Within these direct costs, a mean of EUR 348 (SD 361) was related to thrombosis prophylaxis, accounting for 3% of direct costs. Mean overall cost was EUR 11 926 (SD 2 481), including 6% indirect costs of productivity loss. Extended thrombosis prophylaxis was observed in the usual care setting of the study and associated with low incidence of symptomatic DVT. Thrombosis prophylaxis is — within the considerable economic burden of joint replacement surgery — a relatively small cost component.
Immunohistochemical determination and grading of CerbB-2 expression in breast cancer: correlation with interpectoral, apical nodal involvement and other prognostic factors
Authors: Çelik Alper , Ebru Arabacı I. , Erkorkmaz Unal , Kutun Suat , Aslan Sabahattin , Pak Isın , Çetin Abdullah
Published: January 2007

We aimed to investigate the correlation between quantitative CerbB-2 expressions with conventional prognostic factors, and distinct nodal involvement in patients with invasive breast carcinoma. One hundred fifty seven consecutive breast carcinoma patients were retrospectively analysed. Level I–II, Level III, and Rotter (Interpectoral) group lymph nodes were separately examined and recorded. For each patient estrogen receptor (ER), progesteron receptor (PR), CerbB-2, P53 status were defined using immunohistochemistry. Age, tumor localisation, menopausal status, grade and the presence of intraductal component were also recorded. CerbB-2 expression did not correlate with age, localisation and menopausal status. There was a reverse, but weak correlation with tumor size and CerbB-2 expression (p=0.034). In subgroup analysis of CerbB-2 positive cases, the magnitude of CerbB-2 positivity did not correlate with tumor size (p=0.551). In univariate analysis CerbB-2 expression did not correlate with nodal involvement in Level I-II, and Rotter. In subgroup analysis of patients with positive CerbB-2, positivity of CerbB-2 linearly increased with the number of positive lymph nodes in Level I-II, and this difference was significant (p=0,039). There was a significant correlation between CerbB-2 expression and Level III nodal metastases (p=0.005). But this correlation was not significant among CerbB-2 positive patients (p=0.82). P53, PR positivity and the presence of intraductal component did not differ according to oncogene expression. We detected a reverse correlation with ER positivity and CerbB-2 positivity (p=0.011). It is concluded that quantitative expression of CerbB2 positivity increases with nodal involvement in Level I–II axillary lymph nodes, and ER. Also, CerbB-2 positivity is more common among patients with Level III lymph node metastases.
Paradoxical effect of sodium valproate that aggravates epilepsy of MELAS in a patient with A3243G mutation of the mitochondrial DNA
Authors: Chen Yi-Min , Lin Chih-Ming , Thajeb Peterus
Published: January 2007

Epilepsy is an associated feature of patients with the syndrome of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). A substitution at nucleotide position 3243 A>G of the mitochondrial DNA is the most common mutation encountered both in Caucasians and in Chinese/Taiwanese. We herein report a 38-year-old man with A3243G mutation of the mitochondrial DNA whom developed MELAS. The manifestation of his focal motor epilepsy was aggravated by use of sodium valproate (VPA). The mechanism of this paradoxical effect is proposed.
Monocyte and neutrophil direct counts correlate with C-reactive protein plasma concentration in patients with acute pancreatitis
Authors: Naskalski Jerzy , Maziarz Barbara , Kusnierz-Cabala Beata , Dumnicka Paulina , Panek Józefa
Published: January 2007

Acute pancreatitis (AP) is associated with the intensive inflammatory response in white blood cells (WBC) and C-reactive protein (CRP). This paper presents the relationship between the CRP plasma concentration and the direct counts of peripheral WBC in AP during the initial five days. The study consisted of 56 patients with AP, 36 patients with mild form of AP and 20 patients with severe form of AP. ABX VegaRetic hematological analyzer was used to perform the count of blood cells, and the immunonephelometric method was performed to measure the CRP concentration levels. AP patients presented with WBC count values in the range of 3.2 − 22.4 × 103/µl and CRP concentration levels in the range 3.3 − 599.8 mg/l. The WBC count correlates with CRP levels during the entire observation period. The relationship of CRP and WBC is expressed in the following regression equation: WBC (103/µl) = 3.66 + 1.40 × logeCRP (mg/l). The highest median neutrophil count (8.15 × 103/µl) was observed on the first day. The count decreased to 5.27 × 103/µl on the fifth day. The most substantial finding in this study involved the values found for the monocytes and CRP (r= 0.53; p<0.001). Day two and day three were the highest (r=0.59, p<0.001). On day two, the regression equation for this relationship is: Monocytes (103/µl) = −0.34 + 0.21 × logeCRP(mg/l). The correlation between direct monocyte count and plasma CRP concentration in AP reflect a CRP-dependent stimulation of IL-6 release from activated blood monocytes.
Human leukocyte antigen associations in Finnish liver transplantations due to primary sclerosing cholangitis and primary biliary cirrhosis
Authors: Matinlauri Irma , Nurminen Markku , Höckerstedt Krister , Isoniemi Helena
Published: January 2007

A genetic predisposition has been suggested in primary sclerosing cholangitis (PSC) and primary biliary cirrhosis (PBC). The aim of the study was to evaluate human leukocyte antigen (HLA) frequencies and HLA associations in Finnish PSC and PBC patients. The relative frequencies of HLA-A,-B, and-DR antigens were compared between patients with PSC (n=50), or PBC (n=89), transplanted due to end-stage liver disease, and healthy members in the Finnish bone marrow donor registry (n=10000). Prevalence differences, prevalence ratios and the associated large-sample significance probabilities (2-sided P-values) and 95% confidence intervals were calculated.

We found a strong positive association between PSC and HLA-B8 and-DR3, and a weak positive association between HLA-A1 and PSC. HLA-DR3 also had a weak positive association with PBC, and a weak negative association between HLA-DR5 and PBC was found. In conclusion, HLA-B8, and-DR3 are susceptible for progressive liver disease in PSC, and HLA-DR3 may also be susceptible for disease progression in PBC. HLA-DR5 may be protective against severe PBC.
A case with full clinical manifestations of Dorfman-Chanarin syndrome
Authors: Çuhaci Fatma , Mutluay Rüya , Aksakal Burhan , Erten Yasemin
Published: January 2007

Dorfman-Chanarin syndrome (DCS), is a rare, autosomal recessive disorder associated with lipid metabolism. It is characterized by ichthyosiform nonbullous erythroderma, lipid vacuoles in peripheral leukocytes and variable involvement of organs. We report a Turkish man with the complete syndrome, who described family history of ichthyosis. To best of our knowledge this is the sixth case from Turkish origin to date. In addition to congenital ichthyosis he had also strabismus, horizantal nystagmus, bilateral neurosensory hearing loss, hepatomegaly and splenomegaly. Liver biopsy revealed hidrophic degeneration in hepatocytes, steatosis, enlargement and inflammation in portal areas and portal central fibrosis, consistent with cirrhosis. Write stained peripheral blood smear examination revealed lipid vacuoles in all of the neutrophils consistent with Jordan’s anomaly. We think that, it is essential to evaluate the peripheral blood smear of the patients with ichthyosis and also patients with DCS should be informed and warned about the results of consanquinous marriage.
Spectrophotometric determination of microamounts of quercetin based on its complexation with copper(II)
Authors: Kostić D. , Miletić G. , Mitić S. , Rašić I. , Živanović V.
Published: January 2007

The complexation process of the transition metal Cu(II) with quercetin was studied. The investigation was conducted spectrophotometrically in ethanol at the maximum absorption wavelength of 458.5 nm. Cu(II)—quercetin complex composition (1: 1) was determined using the Job, Harvey—Manning, and mole ratio methods. Complex stability constant was calculated by the Job and mole ratio methods and the respective logarithm values were 7.53 ± 0.25 and 7.44 ± 0.03. A new method for quantitative determination of the quercetin content in solution was developed in this work. At the optimal conditions quercetin was determined in concentrations ranging from 0.202 to 1.006 µg cm−3 with relative standard error of 2.5 % to 5.5 %. The lower detection limit was 0.067 µg cm−3. The method was found very accurate, reproducible, and sensitive, capable to determine microamounts of quercetin in pharmaceutical preparations.
Oxygen evolution on Ti/Co3O4-coated electrodes in alkaline solution
Authors: Palmas S. , Ferrara F. , Pisu A. , Cannas C.
Published: January 2007

The electrochemical performances of Co3O4 nanopowders, obtained by the sol-gel method, were investigated and compared with those of commercial Co3O4 powders, for oxygen evolution reaction in alkaline solution. The active oxide powder was mixed with teflon and assembled on Ti substrate to form thin catalyst film. Cyclic voltammetry, polarization curves, and electrochemical impedance spectroscopy were used to assess the mechanism of oxygen evolution reaction, chemical structure, and morphology of the catalyst.
The zeta potential of kaolin suspensions measured by electrophoresis and electroacoustics
Authors: Greenwood R. , Lapčíková B. , Surýnek M. , Waters K. , Lapčík L.
Published: January 2007

The zeta potentials of kaolin dilute and concentrated suspensions were monitored using the techniques of electrophoresis and electroacoustics, respectively. The effect of addition of salt (KCl), a polymer material (Triton X-100), and an anionic surfactant (sodium dodecyl sulphate, SDS) on the suspension properties was investigated by electrophoresis. Electroacoustics was employed for the measurement of zeta potentials for the highest possible kaolin content in suspension and the effect of dilution. The effect of aging of a freshly prepared sample and kaolin isoelectric point was also studied. Using both techniques it was noted that there was no isoelectric point, just a maximum value in the magnitude of the kaolin suspension zeta potential. These maxima were observed also in the presence of Triton X-100 and SDS. An increase of the concentration of KCl and SDS in suspension shifted the maxima towards more acidic values, while in the presence of Triton X-100 the position of the zeta potential maxima remained constant. Electroacoustic techniques revealed that a freshly prepared concentrated suspension requires about six hours to equilibrate to achieve a steady zeta potential. Diluting the concentrated suspensions led to decrease of the zeta potential as ions bound to the surface desorbed and screened the surface charge. The zeta potential maxima remained unchanged even after heating the powder in an oven at 200°C (to remove any organic material) thereby suggesting that the most likely explanation for the maxima is isomorphic substitution.
Fluidization behavior of oil-contaminated sand
Authors: Hartman M. , Trnka O. , Pohořelý M.
Published: January 2007

Hydrodynamic behavior of oil-polluted particles of sand was investigated in transparent glass column. The onset of fluidization of sand beds increased with the oil content of the bed. An increase of cohesive forces related to the higher content of liquid (oil) caused deterioration of the quality of fluidization. An empirical correlation was developed to predict the dimensionless gas velocity that keeps the bed of sticky particles fluidized. Results of this work can be employed for the design of fluidized-bed remediation units for oil-polluted sands and soils.
Software sensors for monitoring of a solid waste composting process
Authors: Bolf N. , Kopčić N. , Briški F. , Gomzi Z.
Published: January 2007

Process identification for composting of tobacco solid waste in an aerobic, adiabatic batch reactor was carried out using neural network-based models which utilized the nonlinear finite impulse response and nonlinear autoregressive model with exogenous inputs identification methods. Two soft sensors were developed for the estimation of conversion. The neural networks were trained by the adaptive gradient method using cascade learning. The developed models showed that the neural networks could be applied as intelligent software sensors giving a possibility of continuous process monitoring. The models have a potential to be used for inferential control of composting process in batch reactors.
Calcined Ni—Al layered double hydroxide as a catalyst for total oxidation of volatile organic compounds: Effect of precursor crystallinity
Authors: Mikulová Z. , Čuba P. , Balabánová J. , Rojka T. , Kovanda F. , Jirátová K.
Published: January 2007

The effect of hydrothermal treatment on properties (crystallinity, porous structure, reducibility, acidity, basicity, and catalytic activity and selectivity in toluene and ethanol total oxidation) of Ni—Al layered double hydroxide precursors and related mixed oxides was examined. The hydrothermal treatment increased considerably both the content of crystalline phase and LDH crystallite size. On the other hand, only a slight effect of the precursor hydrothermal treatment on crystallinity of the related Ni—Al mixed oxides obtained by calcination at 450°C was observed. The reducibility of NiO particles appeared to be hindered considerably compared to the reducibility of pure NiO. Catalytic activity of the Ni—Al mixed oxides prepared from the precursors hydrothermally treated for a short time (4 h) was the highest. The highest amount of acetaldehyde formed during the total oxidation of ethanol, i.e. the worst selectivity was found for the calcined Ni—Al LDH without hydrothermal treatment.
Thermodynamic possibilities and constraints of pure hydrogen production by a chromium, nickel, and manganese-based chemical looping process at lower temperatures
Authors: Svoboda K. , Siewiorek A. , Baxter D. , Rogut J. , Punčochář M.
Published: January 2007

The reduction of chromium, nickel, and manganese oxides by hydrogen, CO, CH4, and model syngas (mixtures of CO + H2 or H2 + CO + CO2) and oxidation by water vapor has been studied from the thermodynamic and chemical equilibrium point of view. Attention was concentrated not only on the convenient conditions for reduction of the relevant oxides to metals or lower oxides at temperatures in the range 400–1000 K, but also on the possible formation of soot, carbides, and carbonates as precursors for the carbon monoxide and carbon dioxide formation in the steam oxidation step. Reduction of very stable Cr2O3 to metallic Cr by hydrogen or CO at temperatures of 400–1000 K is thermodynamically excluded. Reduction of nickel oxide (NiO) and manganese oxide (Mn3O4) by hydrogen or CO at such temperatures is feasible. The oxidation of MnO and Ni by steam and simultaneous production of hydrogen at temperatures between 400 and 1000 K is a difficult step from the thermodynamics viewpoint. Assuming the Ni—NiO system, the formation of nickel aluminum spinel could be used to increase the equilibrium hydrogen yield, thus, enabling the hydrogen production via looping redox process. The equilibrium hydrogen yield under the conditions of steam oxidation of the Ni—NiO system is, however, substantially lower than that for the Fe—Fe3O4 system. The system comprising nickel ferrite seems to be unsuitable for cyclic redox processes. Under strongly reducing conditions, at high CO concentrations/partial pressures, formation of nickel carbide (Ni3C) is thermodynamically favored. Pressurized conditions during the reduction step with CO/CO2 containing gases enhance the formation of soot and carbon-containing compounds such as carbides and/or carbonates.
Death kinetics of Escherichia coli in goat milk and Bacillus licheniformis in cloudberry jam treated by ohmic heating
Authors: Pereira R. , Martins J. , Mateus C. , Teixeira J. , Vicente A.
Published: January 2007

The influence of ohmic heating on the death kinetic parameters of Escherichia coli ATCC® 25922 in goat milk and spores of Bacillus licheniformis ATCC® 14580 in cloudberry jam was investigated and compared with that of conventional heating. Ohmic treatment of goat milk shortened the decimal reduction time D in comparison with the D values obtained at conventional treatment. Similarly, the z value, increase of temperature required for a ten-fold reduction of D, was also lower at ohmic treatment. The death kinetics of Bacillus licheniformis ATCC® 14580 spores in cloudberry jam was also studied employing both types of heat treatment. Similar conclusions were obtained for the D values as in the case of goat milk. However, the differences between the z values obtained for ohmic and conventional heating were not significant.
Topochemical models for anti-HIV activity of 1-alkoxy-5-alkyl-6-(arylthio)uracils
Authors: Bajaj S. , Madan A.
Published: January 2007

Relationship between topochemical indices and anti-HIV-1 (HTLV-III) inhibitory activity of 1-alkoxy-5-alkyl-6-(arylthio)uracils has been studied. Superadjacency, an adjacency-cum-distance-based, topochemical index and Wiener’s, a distance-based, topochemical index were calculated for a set of 36 1-alkoxy-5-alkyl-6-(arylthio)uracils. Resulting data were analyzed and suitable models were developed after identification of the active ranges. Subsequently, a biological activity was assigned to each of the compounds using these models and compared with the reported anti-HIV-1 activity. High accuracy of prediction was observed using these models. Statistical analysis revealed significance of the proposed models as well as a lack of correlation between the topochemical indices employed for the chosen data set.
Acidity, lipophilicity, solubility, absorption, and polar surface area of some ACE inhibitors
Authors: Remko M.
Published: January 2007

Computational chemical methods have been used to correlate the molecular properties of the 10 ACE inhibitors (captopril, enalapril, perindopril, lisinopril, ramipril, trandolapril, quinapril, fosinopril, benazepril, and cilazapril) and some of their active metabolites (enalaprilat, perindoprilat, ramiprilat, trandolaprilat, quinaprilat, fosinoprilat, benazeprilat, and cilazaprilat). The computed pK a values correlate well with the available experimental values. In the dicarboxylic ACE inhibitors, the carboxyalkyl carboxylate group of the ACE inhibitors studied is more acidic than the C-terminal carboxylate. However, at physiological pH = 7.4 both carboxyl groups of ACE inhibitors are completely ionized and the dicarboxyl-containing ACE inhibitors behave as strong acids. The available experimental partition coefficients of these ACE inhibitors investigated are well reproduced by the neural network-based ALOGPs and the fragment-based KoWWiN methods. All parent drugs (and prodrugs), with the exception of fosinopril, are compounds with low lipophilicity. Calculated pK a, lipophilicity, solubility, absorption, and polar surface area of the most effective ACE inhibitors for the prevention of myocardial infarction, perindopril and ramipril, were found similar. Therefore, it is probable that the experimentally observed differences in the survival benefits in the first year after acute myocardial infarction in patients 65 years of age or older correlate closely to the physicochemical and pharmacokinetic characteristics of the specific ACE inhibitor that is used.
Silver as anode in cryolite—alumina-based melts
Authors: Kucharík M. , Chamelot P. , Cassayre L. , Taxil P.
Published: January 2007

The anodic behaviour of silver was investigated in cryolite—alumina-based melt. Silver has a lower melting point (ca. 960°C) than the other metals considered as possible inert materials for aluminium electrolysis. The working temperature used in aluminium industry is approximately 960°C, depending on the melt composition. Therefore, the stability of silver during the anodic process was tested at 870°C in an acidic electrolyte consisting of 65.5 mass % Na3AlF6 + 22.9 mass % AlF3 + 5.7 mass % CaF2 + 3.9 mass % LiF + 2 mass % Al2O3 with the melting point ca. 850°C. The electrolyte without alumina was prepared as well, with the melting point ca. 860°C. The resulting cryolite ratio (CR = n(NaF)/n(AlF3)) for both electrolytes was equal to 1.6. The behaviour of the silver anode was studied by voltammetry measurements. The electrochemical study showed that an oxidation reaction occurred at a potential below the oxygen evolution potential. Silver was not found to be stable under oxygen evolution. The degradation of the silver anode was apparent after electrolysis.
Multicomponent facile synthesis of novel dihydroazolopyrimidinyl carbamides
Authors: Gladkov E. , Sirko S. , Khanetskii B. , Lukinova E. , Desenko S.
Published: January 2007

Number of novel derivatives of dihydrotriazolo-and-tetrazolopyrimidines containing carboxamide group in position 6 were obtained by multicomponent Biginelli-type reaction. The structures of all synthesized compounds were proved by NMR and MS spectral methods. The method of three-component Biginelli-type reaction is well suited for the synthesis of new promising dihydroazolopyrimidines providing a scaffold for screening of biological activity.
Energieeffizienz von Gebäuden und Behaglichkeit in Räumen
Authors: van Treeck Christoph
Published: February 2007

Die Begeisterung war vielen Teilnehmern anzusehen und in den fachlichen Diskussionen spürbar, offensichtlich hatte man auf eine Veranstaltung dieser speziellen Art gewartet, um die “Simulationsgemeinschaft” im deutschsprachigen Raum zusammenzuführen: Unter dem Leitthema “Energieeffizienz von Gebäuden und Behaglichkeit in Räumen” fand im Oktober 2006 an der Technischen Universität München die erste deutsch‐österreichische IBPSA‐Konferenz BauSIM2006 statt. Begleitend wurde eine industrielle Fachausstellung durchgeführt, die das Programm im Sinne einer intensiven Vernetzung mit der Industrie abrundete. Vorliegende Ausgabe der BAUPHYSIK enthält im Hauptteil die erweiterten Artikel einer vom wissenschaftlichen Gremium der Konferenz getroffenen Auswahl aus den rund 90 Tagungsbeiträgen.

IBPSA steht für International Building Performance Simulation Association und ist ein internationales Forum für Anwender, Forscher und Entwickler im Bereich der thermisch‐energetischen, ökologischen und anlagentechnischen Simulation von Gebäuden. IBPSA‐Germany wurde 2004 als regionale Dependance gegründet und besteht derzeit aus rund 80 aktiven Mitgliedern aus Industrie, Forschungseinrichtungen und Universitäten aus dem deutschsprachigen Raum. Die Konferenz BauSIM wird künftig alle zwei Jahre angeboten. Sie soll dabei keine der zahlreichen kleineren etablierten Veranstaltungen ersetzen, sondern die Vielfalt der Fachthemen entsprechend der Ausrichtung der internationalen IBPSA‐Tagungen vereinen.

Seit Anfang 2007 ist die vollständig überarbeitete Homepage www.ibpsa‐germany.org verfügbar, die den Mitgliedern der IBPSA‐Gemeinschaft (Mitgliedschaft kostenfrei) Zugriff auf die Tagungsbeiträge der lokalen Konferenzen gestattet. Weiterhin wird gegenwärtig unter anderem an einem Simulationsratgeber nach dem konzeptionellen Vorbild eines offenen Wiki‐Media‐Systems gearbeitet. Ihr fachlicher Beitrag ist dabei herzlich willkommen!
ComfSim – Interaktive Simulation des thermischen Komforts in Innenräumen auf Höchstleistungsrechnern
Authors: van Treeck Christoph , Wenisch Petra , Borrmann André , Pfaffinger Michael , Wenisch Oliver , Rank Ernst
Published: February 2007

Der Beitrag gibt eine Übersicht über den gegenwärtigen Stand der Entwicklungen eines “Computational Steering” Werkzeuges zur interaktiven Simulation und Bewertung des thermischen Komforts in Innenräumen. Das System besteht aus einem parallelen CFD Rechenkern, einem schnellen 3D Gittergenerator und einer integrierten VR‐basierten Visualisierungskomponente. Das numerische Verfahren basiert auf einem hybriden thermischen Gitter‐Boltzmann‐Verfahren mit Erweiterungen zur Simulation turbulenter konvektiver Raumluftströmungen. Die Nutzung von Techniken des wissenschaftlichen Höchstleistungsrechnens ermöglicht dabei interaktive Veränderungen am geometrischen Modell und an den Randbedingungen zur Laufzeit bei gleichzeitiger Neuberechnung und Darstellung von Ergebnissen. Das Modell wird gegenwärtig um ein Strahlenmodell und ein lokales thermisches Komfortmodell erweitert, das gemeinsam mit Projektpartnern entwickelt wird. Die Anwendung wird anhand der Strömungssimulation des Großraumabteils eines Zuges demonstriert.
Optimierung geothermischer Energiesysteme am Beispiel eines städtebaulichen Entwicklungsvorhabens
Authors: Höfker Gerrit , Winkler Katja , Bracke Rolf
Published: February 2007

Am Beispiel eines städtebaulichen Entwicklungsvorhabens in Bottrop‐Kirchhellen wird eine vollständige Versorgung eines Baugebietes mit Geothermie vorgestellt. Anhand von Simulationen wurden die Lastprofile der Gebäude ermittelt und mit den geothermischen Simulationen verknüpft. Die Heizlastschwankungen in den Gebäuden stehen jedoch den von den Erdwärmesonden zur Verfügung gestellten und nahezu konstanten Wärmemengen entgegen. Daher ist einerseits die Glättung der Lastprofile durch die Kombination verschiedener gebäudetechnischer Konzepte und andererseits der Einsatz von Speichern von zentraler Bedeutung für eine effiziente Nutzung der Geothermie.
Sonnenschutz: Eine generelle Bewertungsmethode – auch für zwischenliegende Systeme – und zwei neue Behänge
Authors: Kuhn Tilmann E.
Published: February 2007

Es wurde ein allgemeines Verfahren zur realistischen Leistungsbewertung von Sonnenschutzmaßnahmen für Fassaden entwickelt. Das Verfahren eignet sich insbesondere für Jalousien und kann entweder unabhängig oder innerhalb von Gebäudesimulationsprogrammen eingesetzt werden. Das neue Verfahren hat sich in der Praxis bereits bei der Planung großer Bürogebäude in Deutschland, Österreich und der Schweiz bewährt. Dieses Verfahren wird in [4] ausführlich dargelegt. Es kann entweder unabhängig (ohne Gebäudesimulation) zum Vergleich verschiedener Fassadensysteme oder innerhalb von Gebäudesimulationsprogrammen eingesetzt werden. In dieser Veröffentlichung wird die Erweiterung der Methode auf Fassaden mit in einer Isolierverglasung integrierten Sonnenschutzsystemen vorgestellt. Bestimmte Teil e des Verfahrens könnten innerhalb von Normen (z. B. EN 13363) oder zur Verbesserung der Genauigkeit von Gebäudesimulationsprogrammen verwendet werden. Praxiserfahrung mit der neuen Methodik führte zu neuen Erkenntnissen, die die Grundlage für zwei neue Produkte bilden. In [5] werden diese neuen Produkte auf der Grundlage der neuen Methodik mit Produkten auf dem Stand der Technik verglichen. Im Rahmen eines von der Veluxstiftung finanzierten Projekts wird das neue Verfahren z.Z. in das Gebäudesimulationsprogramm ESP‐r integriert.
Functionalization of catalase for a photochemical immobilization on poly(ethylene terephthalate)
Authors: Opwis Klaus , Knittel Dierk , Schollmeyer Eckhard
Published: February 2007

The enzyme catalase (EC 1.11.1.6) was covalently immobilized on textile carrier fabrics made of poly(ethylene terephthalate) (PET) by a novel combined wet chemical and photochemical process. The functionalization of catalase with allyl groups succeeds in a wet chemical treatment of the enzyme with allylglycidylether. This modified enzyme was bonded covalently to the textile material by a photochemical immobilization using a monochromatic excimer UV lamp (222 nm). Using this two‐step procedure nearly 60 mg enzyme/g carrier could be fixed durably. The efficiency of the immobilization products was investigated by measuring the enzymatic decomposition of hydrogen peroxide in comparison to the free enzyme. The relative activity of the catalase after the immobilization was nearly 5% compared to the free, not fixed enzyme; however, even after 30 reuses, the modified and immobilized catalase still showed a distinct activity.
A Combined QM/MM Molecular Dynamics Simulations Study of Nitrate Anion (NO3‐) in Aqueous Solution.
Authors: Tongraar Anan , Tangkawanwanit Piyawan , Rode Bernd Michael
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
First Observation of an Inverse Ruddlesden‐Popper Series: (A3n+1ONn‐1)Bin+1 with A: Sr, Ba and n = 1, 3.
Authors: Gaebler Frank , Prots Vurii , Niewa Rainer
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cobalt Centered Trigonal Ln6 Prisms and Mg4 Clusters as Basic Structural Units in Ln4CoMg (Ln: Y, La, Pr, Nd, Sm, Gd—Tm).
Authors: Tuncel Selcan , Hoffmann Rolf‐Dieter , Chevalier Bernard , Matar Samir F. , Poettgen Rainer
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Effect of Rhodium Incorporation in KTiOPO4 Single Crystals Grown from Self‐Flux.
Authors: Bhaumik I. , Ganesamoorthy S. , Bhatt R. , Karnal A. K. , Sundar R. , Wadhawan V. K.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
InAsxSb1‐x Alloy Nanocrystals for Use in the Near Infrared.
Authors: Kim Sang‐Wook , Sujith S. , Lee Bun Yeoul
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Highly Enhanced Luminescence of GdTaO4:Eu3+ Phosphors by Codoping with Zn2+ Ions.
Authors: Gu Mu , Xiao Lihong , Liu Xiaolin , Zhang Rui , Liu Bingjie , Xu Xin
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Multinuclear High‐Resolution NMR Study of Compounds from the Ternary System NaF—CaF2—AlF3: From Determination to Modeling of NMR Parameters.
Authors: Martineau C. , Body M. , Legein C. , Silly G. , Buzare J.‐Y. , Fayon F.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Magnetic Properties and Electronic Structure of the New HfFe6Ge6‐Type HfMn6Ge6 Compound.
Authors: Ihou‐Mouko Hilaire , Mazet Thomas , Isnard Olivier , Malaman Bernard
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
LiMn2‐yMyO4 (M: Cr, Co) Cathode Materials Synthesized by the Microwave‐Induced Combustion for Lithium Ion Batteries.
Authors: Fu Yen‐Pei , Su Yu‐Hsiu , Wu She‐Huang , Lin Cheng‐Hsiung
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Hydrogen Absorption—Desorption in CeNi2.
Authors: Di Chio M. , Livraghi S. , Baricco M.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Crystal Structure of In(OH)(SeO3).
Authors: Paterson Brian , Harrison William T. A.
Published: February 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.