68 research outputs found
A fundamental study on mechanical & physical properties of polymer-modified self-healing mortars using bacteria
No full textA polymer-modified self-healing mortar is a mixture of Portland cement, water, sand, polymer and self-healing material. The polyacrylic ester emulsion (PAE) is used as polymer and as self-healing material bacterial spores from genus Bacillus + calcium lactate is used. The reason why this type of bacteria is used as a component of self-healing material is because of the high alkaline environment inside the mortar. A mortar has a pH value of between 9 and 11. As far as known, only this kind of bacteria can be used as a self-healing agent for mortars. Why a polymer-modified self-healing mortar? This polymer- modified self-healing mortar has an autonomous self-healing mechanism with, a high workability, a high flexural strength and also a high adhision. The experiments that has been performed in this study show that a polymer- modified self-healing mortar is a strong material with and active self-healing. This bacterial self-healing mechanism can heal cracks up to 0.46mm in contrast to the autogenous self-healing (of conventional mortar) of cracks up to 0.18mm. Beside this the fresh mortar showed a high workability. These properties make the polymer-modified self-healing mortar a strong and a more durable mortar. This concept can also be used to produce polymer-modified self-healing concrete.Materials and EnvironmentCivil Engineering and Geoscience
Vapor-Phase Incorporation of Ge in CZTSe Absorbers for Improved Stability of High-Efficiency Kesterite Solar Cells
No full textWe report an approach to incorporate Ge into Cu2ZnSnSe4 using GeSe vapor during the selenization step of alloyed metallic precursors. The vapor incorporation slowly begins at T ≈ 480 °C and peaks at 530 °C, resulting in a Ge-based composition shift inside the previously formed kesterite layer. We initially observe the formation of a Ge-rich surface layer that merges into a homogeneous distribution of the incorporated element during the further dwelling stage of the annealing. This approach is very versatile and could be used in many similar fabrication processes for incorporating Ge into CZTSe-absorber layers. Because the vapor-based composition shift in the layer happens after the formation of the absorber film towards the end of the fabrication process, most process parameters and the precursor structure may not need any significant re-optimization. The careful integration of this step could help to reduce Sn-related deep defects and accompanying VOC losses. The best CZTGSe-power-conversion efficiency obtained in this series is 10.4 % (with EG = 1.22 eV, FF = 54%, JSC = 36 mA/cm2, VOC = 540 mV, VOCdef,SQ = 417 mV). These results demonstrate the potential of this approach for Ge incorporation into kesterite absorbers
Synthesis and characterization of bulk Cu2ZnSnX4 (X: S, Se) via thermodynamically supported mechano-chemical process
No full text
Current Status of Bacillus thuringiensis: Insecticidal Crystal Proteins and Transgenic Crops
No full textDevelopment of Predictive Models using Data Mining Software for R&D Institutes
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Organization Development Experiences . A Case for Enriching HRD through OD
No full textThis article reviews a few definitions of OD and identifies eight characters that are necessary to call an activity or experience as an OD activity or experience. The article then goes on to examine ten case studies (of research, consulting and OD) of what appears like an OD activity in which the author was involved as one of the facilitators for whole system or subsystem and examines each on of them for their appropriateness to be called as OD interventions. The author then goes on to derive some lessons from these experiences. The article outlines also some advantages of using traditional OD approach in various HRD interventions and offers some suggestions for making specific HRD interventions like competency mapping, 360Degree Feedback based leadership Development and Assessment and Development Centers as OD activities. The paper concludes that using an OD approach enriches HRD and yields a good ROI on HRD interventions.
On D-Paracompact spaces
No full textAbstractFollowing Pareek a topological space X is called D-paracompact if for every open cover A of X there exists a continuous mapping f from X onto a developable T1-space Y and an open cover B of Y such that { f-1[B]|B ∈ B } refines A. It is shown that a space is D-paracompact if and only if it is subparacompact and D-expandable. Moreover, it is proved that D-paracompactness coincides with a covering property, called dissectability, which was introduced by the author in order to obtain a base characterization of developable spaces
Hydrogen generation from NaBH<sub>4</sub> hydrolysis using Co-B/AlPO<sub>4</sub> and Co-B/bentonite catalysts
No full textGasification of Crop Residue Briquettes in an Open Core Down-draft Gasifier
No full textGasification of crop residue briquettes was studied in an open core, throatless, down-draft gasifier of 1800 MJ.h-1 capacity. Briquettes of 25, 35 and 55 mm diameters were prepared using sugarcane baggase, cotton stalk and ground nut shell, separately, in a piston press briquetting machine. Series of experiments were conducted to study performance of the gasifier in terms of fuel consumption rate, calorific value of producer gas and gasification efficiency using briquettes of selected crop residue. The performance was compared with the performance data already available for babul wood. The gasifier was found working satisfactorily with the babul wood and briquettes of all the three crop residues of three sizes. The gasification efficiency was highest for groundnut shell briquettes, followed by babul wood, sugarcane baggase briquettes and cotton stalk briquettes. The study revealed that clinker formation was lower and calorific value of the gas higher for gasification of smaller sized biomass briquettes
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