Improving Inorganic Composition of Lignocellulosic Biomass by Water Leaching Pre-treatment for Thermochemical Applications

Worldwide market for new and upgraded solid biofuels from low-quality lignocellulosic biomass residues is rapidly increasing for energy and chemical recovery. However, the inorganic composition of low-quality herbaceous and forest residues severely restricts their valorisation in thermochemical processes. Water leaching pre-treatment is an effective method for reducing inorganic content in lignocellulosic biomass. However, specific research on its implementation and optimization for industrial applications is missing from the available body of knowledge. The main goal of this doctoral work is to improve the basic understanding of water leaching pre-treatment and upgrade its technical feasibility for large-scale applications based on experimental findings. The research work was divided into three steps. In the first step goal was to better understand the effect of basic leaching parameters on pre-treatment efficiency and evaluate the impact of pre-treatment on a range of feedstocks. The goal in the second step was to improve the pre-treatment efficiency by process modification, pilot-scale testing and comparing the results with laboratory findings. In the third step, the effect of leaching pre-treatment was evaluated on ash-fusion behaviour of different biomasses and stepwise pyrolysis product yields. Experimental results show that water leaching successfully removed about 30-100% of troubling elements (K, Na, Cl, N, S, Ca, Mg, P, Si) from different types of biomasses. Consequently, fewer ash- related issues can be expected from the leached biomass in combustion and gasification. Also, higher yields and quality of bio-oil and biochar were achieved after using pre-treated biomass in stepwise pyrolysis. A novel pre-treatment process, “step washing”, was also explicitly developed for practical application and tested on a pilot- scale. Step washing process showed better pre-treatment efficiency than the single step leaching (3-24 hrs) process in much shorter durations (4-15 min). The major contribution of this doctoral work is about improving the understanding of the overall leaching process and modifying it for large-scale applications based on detailed experimental studies. The findings presented in this dissertation will benefit both researchers and practitioners working in the area of biomass pre-treatment, process engineering, and biomass valorisation by thermochemical conversion

Reconfigurable cache architecture

This thesis presents reconfigurable cache architecture and its preliminary evaluation. The work presented here is a part of on going effort at Department of Computer Engineering (Iowa State University), on this architecture. The architecture was initially proposed by Prof. Akhilesh Tyagi and Prof. Arun Somani. The target of this project is a microprocessor that is reconfigurable and utilizes the chip real estate more efficiently than the existing microprocessors. A configurable machine has the ability to customize its characteristics (run time environment) to suit the requirements of the application in execution. All general-purpose machines are configurable by this definition. Configuration is achieved by the operation system (virtual memory, loading specific drivers etc.). Such environment setting forms the configuration for the application in execution. In this thesis we present an architecture that extends configurability to the processor hardware. Reconfigurable cache architecture allows the amount and the nature of execution logic of a processor to be changed to suit the characteristics of the application in execution. There has been an increasing trend towards larger on-chip caches over the years. While these large caches do reduce the gap between the processor and the memory performance, the advantage does not scale well with the amount of resources allocated to cache. The caches take a huge portion of the processor real estate. Our studies with multi-media benchmarks show that not more than 20 % of the cache is utilized at a time for large caches. This architecture seeks to better utilize this chip area by utilizing the same chip area for caching and for computation

Alteration of cardiovascular autonomic activity in type 2 diabetes mellitus

Background: Diabetes mellitus (DM) is a clinical syndrome characterized by hyperglycaemia due to absolute or relative insulin deficiency. Cardiovascular autonomic neuropathy (CAN) invokes potentially life-threatening outcomes especially in poorly controlled diabetic patients. This study was to evaluate the prevalence of CAN in diabetic patients and its relationship with QTc interval.Methods: This observational study of two year duration was included total 123 patients of more than 30 (thirty) years and up to 60 (sixty) years of age who were presented with diabetic mellitus (DM) those were evaluated for CAN using four distinct clinical tests-Resting heart rate (RHR), test for orthostatic hypotension (OH), hand gripping test (HGT) and QTc interval on ECG. Data were analyzed with statistical package for social sciences (SPSS), version 23.Results: The mean age of all 103 studied patients was 48.94±8.69 years; Mostly patients belong to 50-60 years of age and the majority was males (69.0%). Out of 103 72.8% patients were reported with CAN (51 males and 24 females) and without CAN were 27.2.0% (20 males and 8 females), 36% of patients of Definite Parasympathetic neuropathy, 25% Normal and 20% of Sympathetic neuropathic patients. HbA1c level increases the danger of CAN also. QTc interval is a reliable indicator for the presence of CAN.Conclusions: Duration of diabetes is directly proportional to the prevalence of CAN. Various cardiac autonomic function tests detect CAN

Vertex-Fed Hexagonal Antenna with Low Cross-Polarization Levels

Probe-fed hexagonal patch antenna suffers from impedance mismatch especially when feed is located at one of the vertices of polygon. Hexagonal planar antennas also suffer from high cross polar levels. This paper proposes a method to overcome impedance mismatch and to increase co-polarization level by reducing ground plane. Vertex feeding is demonstrated in this paper to establish improvement in impedance values more clearly. The impedance at any vertex of a hexagonal patch is too high when compared to the characteristic impedance of the probe. Three vertex-fed hexagonal antennas are developed to demonstrate the effect of ground plane reduction within C-Band. The proposed technique can be optimized to match the impedance and achieve good return loss where monopole radiation characteristics are not an issue. A vertex-fed reduced ground hexagonal antenna is proposed here that operates around 5 GHz with a frequency span of 600 MHz. Thus, the proposed antenna is quite suitable for indoor wireless LAN (UNII-1) applications

Probe-Fed Polygonal Patch UWB Antennas

The chapter deals with the design of probe-fed planar antennas to operate at wider bands and techniques to improve peak or boresight gain using reflectors. The phenomenon of frequency excitation in dual-band, that is, C-band and X-band using the technique of partial removal of the ground plane, is well demonstrated here. The impedance bandwidth achieved by the sample antenna is 285 MHz and 380 MHz, respectively. The reduced ground plane technique is further exploited along with modifications in the shape of the ground plane to cover the entire ultra-wideband (UWB) range in a probe-fed hexagonal monopole antenna. Due to the existence of higher modes and especially when fed with a probe, UWB antennas are only capable of providing mediocre gain at higher frequencies. An approach to increase the probe-fed hexagonal UWB antenna’s peak gain involves the utilization of an appropriate reflector. The antenna is given an artificial magnetic conductor (AMC)-based reflector, which increases the peak gain as well as boresight gain across a band ≤ UWB. Peak and boresight gains of 3.74 dB and 5.5 dB, respectively, are observed with AMC. The equivalent circuit model and simulated impedance results of the sample antennas are validated with the measurement results

Spatio-temporal Analysis of Open Waste Dumping Sites Using Google Earth : A Case Study of Kharagpur City, India

Google Earth provides high-resolution satellite images over a long period of historical time period which can be used to study land use/land cover (LULC) changes in any area over an extended period of time. In this study, Google Earth Pro was used to identify problems with current locations of solid waste dumping sites and conduct a time-series analysis of the areas occupied by waste dumping sites in Kharagpur city. Five dumping locations were studied of which three are official dumping sites, one is an illegal dumping site and the last one is an official dumping site which was cleaned in 2015. Satellite images of the same dumping locations were taken to evaluate changes in the areas of the dumping sites from 2010 to 2017. The results of the study show that most of the sites are situated very close to an airbase runway, railway line, residential area or highway/road which is in contravention of regulations. Time-series analysis shows that the sizes of all dumps have varied significantly with respect to time except for the unauthorized dumping site. The reasons behind the fluctuations in area are frequent burning of garbage and partial clean-up of the site due to local complaints. The methodology used in this study can be extended to an entire city or even several cities to find problems related to the existing illegal or official waste dumping site within a specific time period.acceptedVersionPeer reviewe

Environmental Impacts of Sandstone Quarrying and Its Waste : A Case Study of Jodhpur, India

Google Earth provides high resolution satellite images over a long period of time which can be used in various environmental and climate studies. In the present study, Google Earth was used to evaluate incremental trends in the quarrying area and associated environmental impacts. Keru region near Jodhpur city, India was selected as the study area for the present study. Time series analysis was done from 1990 to 2016 to evaluate increments in the quarrying area. After 2007, recently built stone cutting units and dumping locations were also observed. Land degradation around the quarrying zone was also quantified from 2007 to 2016 using Google Earth imagery. After time series analysis, extensive site survey was also done to check and verify different quarrying and dumping practices in the study area and their effect on the environment. The results of the time series analysis show 4.55 times increment in study area from 1990 to 2016, with a linear relationship between increment in study area along with emergence of new cutting units and waste dumping sites. Since 2007, about 71.4 hectare of agricultural land was destroyed due to quarrying activities out of which 24.3% of the land is now assimilated in sandstone quarries. Results of the site survey show that major reasons for onsite and nearby environmental degradation were use of improper machinery and vehicles; haphazard and unsystematic quarrying over a long period of time; and dumping of quarry waste.publishedVersionPeer reviewe

Alcoholism with central pontine demyelination: a case report

Central pontine myelinolysis is a non-inflammatory demyelinating disease characterized by loss of myelin with relative neuron sparing, associated with rapid correction of hyponatremia and sometimes hypernatremia or chronic alcoholism. We are reporting a case of 52 year old male patient who was chronic alcoholic from past 20 years, presented to us with complaints of altered sensorium and dysarthria of 5 days duration .He was investigated and diagnosed as case of central pontine myelinosis associated with chronic alcoholism

Toward Peptide Nucleic Acid (PNA) Directed Peptide Translation Using Ester Based Aminoacyl Transfer

Peptide synthesis is a fundamental feature of life. However, it still remains unclear how the contemporary translation apparatus evolved from primitive prebiotic systems and at which stage of the evolution peptide synthesis emerged. Using simple molecular architectures, in which aminoacyl transfer of phenylalanine occurs either between two ends of a PNA stem loop structure, between two PNAs in a duplex, or between two PNAs assembled on a PNA template, we show that bona fide template instructed phenylalanine transfer can take place. Thus, we have identified conditions which allow template assisted intermolecular aminoacyl transfer using simple ester aminolysis chemistry primitively analogous to the ribosomal peptidyl transferase reaction in the absence of anchimeric assistance from ribose and ribosome catalysis. These results help define the minimum chemical boundary conditions for the translation process and also give insight into the possibilities for the prebiotic emergence of RNA-independent translation