Evaluation of Shell and Pulp Lifters in Semiautogenous Mills with the Dem Simulation

Today's high capacity semiautogenous grinding (SAG) mills expend vast amounts of energy and in doing so consume tons of steel balls and shell liners. The energy efficiency of these mills can be directly examined by looking at the motion of rocks and grinding balls inside the mill. The make-up of the charge and the design of lifter bars atta-ched to the inside of the mill shell can be chosen parti-cularly to maximize the mass of ore fractured per unit of energy spent. At the same time, the unnecessary collisions of balls against the mill shell can be prevented. Further more, the cascading charge flow can be altered in a way to maximize grinding efficiency. The harsh environment in the mill prevents any instrumentation in the interior of the mill. Instead, the simulation of charge motion became a practical tool with the emergence of the discrete element method (DEM)

Correlation and path coefficient analysis of yield components in cocoa (Theobroma cacao L.)

Phenotypic correlations and their direct and indirect effects were estimated with twenty traits of 151 cocoa trees using path analysis. A high coefficient of phenotypic correlation was found between, tree girth, pod length, pod weight, pod volume, number of beans per pod, wet bean weight per pod before and after fermentation, dry bean weight per pod, single wet bean weight, single dry bean weight, number of pods per tree and polyphenol content exhibited highly significant positive correlation with the dry bean yield per tree. However, path analysis revealed that jorquetting height, tree girth, number of fan branches, pod girth, pod volume, pod wall thickness at furrows, wet bean per pod weight after fermentation, dry bean weight per pod, number of pods per tree, shelling percentage, fat content and polyphenol exhibited significance at high level in positive direction

Papillary thyroid cancer: sporadic or inherited?

Background: Papillary thyroid cancer (PTC) is one of the most common thyroid malignancies, with an increase in incidence rates over the past few decades. Although the exact cause of thyroid cancer in most patients is still unclear, the possibility of genetic predisposition to PTC cannot be overlooked. Here, we report a case study of PTC, in which the family was extensively affected, with each family member diagnosed with either benign or malignant thyroid neoplasms, or functional thyroid disorder.Method: A 57-year-old white female with a past medical history of hypothyroidism, and a significant family history of multiple thyroid cancers, was found to have new onset thyroid nodules during a routine screening ultrasound. Fine needle aspiration revealed suspicious papillary carcinoma (follicular variant). The patient underwent total thyroidectomy.Results: The histology report revealed total colloid nodules in the right lobe with focal calcification, lymphocytic thyroiditis, and two foci of papillary microcarcinoma. The patient subsequently underwent radioactive iodine ablation therapy, along with pilocarpine and thyrogen injection.Conclusion: This case study illustrates the need for awareness of the possibility of genetic predisposition to, as well female preponderance of, familial PTC.Keywords: papillary thyroid cancer, familial, sporadic, genetic associatio

Environment-Dependent Breakage Rates in Ball Milling

Breakage rates of particles in a ball mill change with instantaneous particle size distribution in the mill. Slurry density and the presence of a grinding aid also affect breakage rates substantially. The effect of these variables, which constitute the mill environment, on breakage rates has been quantified with a unique estimation method known as the G-H method. This method enables the estimation of breakage rates of all size intervals by a simple linear graphical scheme. In general, breakage rates of coarse particles increase in the presence of fine particles, while the rates of fine particles remain relatively unaffected. Grinding aid restores the fluidity of the solid-liquid mixture even at very high percent solids and so the rate of grinding returns to ‘normal’ from ‘erratic’ behavior

Development of a multicomponent-multisize liberation model

Journal ArticleThis paper is concerned with the development of a kinetic model for mineral liberation by grinding. Existing population balance size reduction models are extended to include two minerals with an arbitrary number of locked particle fractions. The validity of this approach to liberation modelling is demonstrated for the ball mill grinding of a copper ore in batch laboratory and continuous pilot plant mills

Variability for Qualitative and Quantitative Traits in Glory Lily (Gloriosa superba L.)

Glory lily (Gloriosa superba L.) is one of the major medicinal plants of India cultivated for its seeds which are exported to developed countries for pharmaceutical use. Identifying germplasm is an important component for efficient and effective management of plant genetic resources. Variability for qualitative and quantitative traits was investigated in 18 genotypes of G. superba collected from different regions of Tamil Nadu and Andhra Pradesh. For qualitative traits, these genotypes were subjected to diversity analysis based on NBPGR descriptors. Fourteen qualitative and twenty quantitative traits of G. superba were evaluated to assess morphological variations among the genotypes collected. In qualitative traits, a large number of genotypes of the 18 clustered together, at 77% similarity in two clusters. Dendrogram constructed on the basis of twenty quantitative traits for the same set of genotypes did not reveal any clear pattern in grouping, and the genotypes were grouped into seven different clusters. Cluster analysis based on qualitative and quantitative traits revealed a different group of genotypes for each of the data-set. This clearly indicated that less variation existed between genotypes with respect to morphological traits. These easily observable morphological traits are useful tools for preliminary evaluation, because, they offer a fast and reliable approach for assessing extent of diversity in G. superba genotypes

Estimation of Anti-hepatic Viral Compounds in Phyllanthus amarus in vitro Cultures

Phyllanthus amarus Schum. and Thonn (Euphorbiaceae) is recognized commonly as 'Bhumyamlaki' in the Indian system of medicine and has been traditionally used for treating a variety of ailments, including hepatic disorders. Anti-hepatic viral compounds such as phyllanthin and hypophyllanthin were evaluated in different types of in vitro cultures of Phyllanthus amarus by High Performance Liquid Chromatography (HPLC). Among the cultures, in vitro plantlets regenerating from the nodal segment recorded higher amounts of phyllanthin and hypophyllanthin

Analyzing Variability in Coleus forskohlii Briq. Using RAPD Markers

Coleus forskohlii Briq. is an indigenous medicinal plant with high traditional use in India. Genetic analysis of 37 diverse C. forskohlii genotypes was performed using 25 RAPD primers, which yielded 117 bands, of which 60 (51.28%) were polymorphic providing an average of 3.75 bands per primer. There were no genotype-specific products. The number of bands per primer varied from 1 (OPZ 8&16) to 7 (OPZ 11). Similarity matrix was constructed using Jaccard's Coefficient and the data matrix of coefficient of similarity was subjected to cluster analysis using unweighted pair group methodology with arithmetic average (UPGMA). Cluster analysis resulted in grouping of 37 genotypes into two major clusters. The results indicated that RAPD could be used for genetic diversity analysis in C. forskohlii using higher number of primers as it is reliable, easy, rapid and cost-effective

Symbolic Exploration of Transition Hierarchies

In formal design verification, successful model checking is typically preceded by a laborious manual process of constructing design abstractions. We present a methodology for partially - and in some cases, fully - bypassing the abstraction process. For this purpose, we provide to the designer abstraction operators which, if used judiciously in the description of a design, structure the corresponding state space hierarchically. This structure can then be exploited by verification tools, and makes possible the automatic and exhaustive exploration of state spaces that would otherwise be out of scope for existing model checkers. Specifically, we present the following contributions: - A temporal abstraction operator that aggregates transitions and hides intermediate steps. Mathematically, our abstraction operator is a function that maps a flat transition system into a two-level hierarchy where each atomic upper-level transition expands into an entire lower-level transition system. For example, an arithmetic operation may expand to a sequence of bit operations. - A BDD-based algorithm for the symbolic exploration of multi-level hierarchies of transition systems. The algorithm traverses a level-n transition by expanding the corresponding level-(n-1) transition system on-the-fly. The level-n successors of a state are determined by computing a level-(n-1) reach set, which is then immediately released from memory. In this fashion, we can exhaustively explore hierarchically structured state spaces whose flat counterparts cause memory overflows. - We experimentally demonstrate the efficiency of our method with three examples - a multiplier, a cache coherence protocol, and a multiprocessor system. In the first two examples, we obtain significant improvements in run times and peak BDD sizes over traditional state-space search. The third example cannot be model checked at all using conventional methods (without manual abstractions), but can be analyzed fully automatically using transition hierarchies