Pot-in-pot reactions: a simple and green approach to efficient organic synthesis

Incompatible organic reactions impede efficient green synthesis by making multi-component or cascade reactions a big challenge. This review highlights pot-in-pot reactions (multiple reactions carried out in one pot by separating key reactions with a thin polymeric membrane) as an efficient, green synthetic alternative to conventional synthesis. We discuss the advantages of homogeneous processes to develop new cascade reaction sequences by reviewing the use of polymeric thimbles as selective semi-permeable walls. These thimbles allow small organic molecules to diffuse through while retaining polar reagents, polar solvents, and/or organometallic catalysts. The dynamic and versatile nature of this technique is demonstrated by performing 2- and 3-step cascade reactions in one glass pot. A pot-in-pot reaction approach to synthesis circumvents the need to isolate intermediates, or handling of toxic/unpleasant by-products, therefore enabling synthesis of otherwise challenging molecules, improving the efficiency, or enabling greener approaches to modular synthesis

Quota Admission Policy and Its Impact on Equitable Access to Quality Secondary School Education in Kakamega County, Kenya

Through its secondary school quota admission policy, the Ministry of Education in Kenya endeavors to ensure equitable access to quality secondary school education opportunities by placing students into various categories of secondary schools based on sub county quotas as well as public-private primary schools quotas. The quota admission policy is intended to ensure that students from lower socioeconomic status are given opportunities to attend national and extra county secondary schools. However, every year after the initial placement of students into various categories of secondary schools about 23.01% of students fail to join secondary schools of initial placement but seek transfer to join other schools through a replacement process. In this regard, the aim of this study was to examine the impact of quota admission policy on equitable access to quality secondary school education in Kakamaga County in Kenya. The specific objectives of this study were; (i) to determine the impact of students’ type of primary school attended on equitable access to quality secondary school education opportunities, (ii) to determine the impact of students’ sub county of residence on equitable access to quality secondary school education opportunities, (iii) to determine the impact of students’ socioeconomic status on equitable access to quality secondary school education opportunities. Stratified sampling, proportional sampling and simple random sampling techniques were used to arrive at a sample of 280 students from 2 National schools, 480 from 6 Extra County schools, 500 from 7 County schools, and 960 from 30 Sub County secondary schools. The sample also included 45 principals. Descriptive research design was adopted for the study. Questionnaires were used to collect data and descriptive statistics used to analyze the collected data. The study findings indicated a higher representation of students who attended private primary schools in the national (63.1%) and extra county (56.5%) secondary schools compared to students who attended public primary schools. The results further indicated that students from upper (57.3%) and middle (50.8%) socioeconomic status were highly represented in the national and extra county secondary schools compared to students from lower socioeconomic status. The study recommends that the government should address factors that impede students who attend public primary schools especially those from lower socioeconomic status to join national and extra county secondary schools. Keywords:quota selection admission policy, equitable access, quality secondary education, socioeconomic status, initial placement, replacement. DOI: 10.7176/JEP/13-32-07 Publication date: November 30th 2022

Factors Influencing Strategic Information Systems Implementation In Government Parastatals: A Case Of Kenya Forest Service, Mau Forest Conservancy

The operations of parastatals could be greatly enhanced by the wellfocused application of information systems to support improvements in productivity, management effectiveness and ultimately, the quality of services offered to citizens. Assessing the strategies of information systems (ISs) implementation has been identified as one of the most critical issues in IS field. However, studies relating to this issue within the context of kenyan parastatals are few and lack the ability to propose a major set of factors influencing the strategic IS implementation. The study sought to determine the influence of top management support, expertise, infrastructure and enduser training on strategic information systems implementation at Kenya Forest Service. The study adopted descriptive research design using a sample of 262 drawn from a population of 831 staff of the Kenya Forest Service, Head of Conservancy Mau selected using stratified and simple random sampling technique. Data was collected by questionnaires and analysed by descriptive statistics and multiple regression analysis. The findings revealed that the relationship of top management support, expertise, end-user training and infrastructure explain a strong change in strategic information systems implementation. The study concluded that to ensure strategy is implemented as intended, senior executives must endevour to persuade the employees of their ideas and that IT professionals' technical backgrounds is critical both during the selection and acquisition of complex IT system and for the implementation of information system into adopting organizations

Synthesis of Liquid Core−Shell Particles and Solid Patchy Multicomponent Particles by Shearing Liquids Into Complex Particles (SLICE)

We report a simple method that uses (i) emulsion shearing with oxidation to make core–shell particles, and (ii) emulsion shearing with surface-tension driven phase segregation to synthesize particles with complex surface compositions and morphologies. Subjecting eutectic gallium–indium, a liquid metal, to shear in an acidic carrier fluid we synthesized smooth liquid core–shell particles 6.4 nm to over 10 μm in diameter. Aggregates of these liquid particles can be reconfigured into larger structures using a focused ion beam. Using Field’s metal melts we synthesized homogeneous nanoparticles and solid microparticles with different surface roughness and/or composition through shearing and phase separation. This extension of droplet emulsion technique, SLICE, applies fluidic shear to create micro- and nanoparticles in a tunable, green, and low-cost approach

Classification and influence of agricultural information on striga and stemborer control in Suba and Vihiga Districts, Kenya

This paper reports on findings of a study to examine the sources used by farmers in search of agricultural information on striga and/or stemborers control technologies and factors that influence acquisition of such information in Western Kenya region. A random sample of 476 households in Suba and Vihiga districts were interviewed and 15 information pathways were identified. Using principle component analysis (PCA) to derive few latent variables that encapsulate maximum variance in the pathways, two components (latent variables) proxying for ‘agricultural knowledge’ were extracted. Type I-knowledge (first component) loaded heavily with sources that had ‘group’ information searching. Type II-knowledge (second component) loaded heavily with sources requiring individual farmer search. Both types of knowledge positively and significantly influenced the likelihood of households using improved technology to control stemborer, while only Type-II knowledge and social economic factors were important in influencing the farmers’ likelihood of using an improved technology to control striga. This study shows that information is an important factor in the households’ likelihood of using improved technologies in the control of striga and stem borer in Vihiga and Suba, Kenya. Methods of individual interaction are important to striga control.Agricultural information, improved technology, striga, stemborers, control technologies, Kenya, Agricultural and Food Policy, Community/Rural/Urban Development, Demand and Price Analysis, Farm Management, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Institutional and Behavioral Economics, International Relations/Trade, Marketing, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies, Resource /Energy Economics and Policy,

Complexity and Opportunities in Liquid Metal Surface Oxides

The ability of metal alloys to rapidly oxidize in ambient condition presents both a challenge and an opportunity. Herein, we focus on opportunities buried in the passivating oxide of liquid metal particles. Recently described sub-surface com-plexity and order present an opportunity to frustrate homogeneous nucleation hence enhanced undercooling. Plasticity of the underlying liquid metal surface offers an autonomously repairing sub-surface hence the lowest E0 component domi-nates the surface unless stoichiometrically limited. This plasticity provides an opportunity to synthesize organometallic polymers that in situ self-assemble to high aspect ratio nanomaterials. An induced surface speciation implies that under the appropriate oxidant tension, the oxide thickness and composition can be tuned, leading to temperature-dependent composition inversion and so-called chameleon metals. The uniqueness of demonstrated capabilities points to the need for more exploration in this small but rather complex part of a metal alloy

Gum Arabic as an Admixture in Modified Concrete Mixed with Calcined Kaolin

The use of calcined kaolin (CK) as a cementitious material in construction has attracted the interest of various researchers due to its environmental, mechanical, and physical qualities, all of which contribute to the lowering of cement usage. Studies have reported numerous problems associated with its use in concrete, apart from the ecological benefit that CK can provide. For instance, there is an issue of increased water demand due to smaller particle size, which generates much more heat in concrete, which has a detrimental effect on the mechanical and physical properties of concrete. This paper presents the analysis of an investigation aimed at using gum Arabic (GA) as a biopolymer admixture and calcined kaolin as a partial replacement of cement to improve the mechanical properties and durability of concrete. GA proportions ranged from 0 to 1% by weight of cement. Calcined kaolin (CK) was used to replace 5, 10, 15, 20, 25, and 30% of the cement content, respectively. Compressive strength, splitting tensile strength, density, strength loss, and weight loss tests were all performed to validate the structural performance of the modified concrete. The compressive tests, performed after 28 days from the time the mixture was made, demonstrated that the maximum percentage of CK that could replace cement without affecting the mechanical properties of concrete was 20%. Beyond 20%, concrete does not exhibit good compressive strength properties. The results also revealed decreased compressive strength and splitting tensile strength tests as the percentage of CK increased. After 56 days, compressive strength at 5% CK and 10% CK increased slightly by 0.743% and 1.162 %, respectively, compared to the control sample. The inclusion of 0.8%GA increased the compressive strength by 8.94% compared to the control sample (0%CK + 0%GA + 100%OPC) after 56 days. The results of durability tests showed that 0.6% GA had a higher compressive strength than other percentages containing GA. Doi: 10.28991/CEJ-2022-08-05-010 Full Text: PD

Rapid acquisition of wideline MAS solid-state NMR spectra with fast MAS, proton detection, and dipolar HMQC pulse sequences

The solid-state NMR spectra of many NMR active elements are often extremely broad due to the presence of chemical shift anisotropy (CSA) and/or the quadrupolar interaction (for nuclei with spin I \u3e 1/2). These NMR interactions often give rise to wideline solid-state NMR spectra which can span hundreds of kHz or several MHz. Here we demonstrate that by using fast MAS, proton detection and dipolar hetero-nuclear multiple-quantum (D-HMQC) pulse sequences, it is possible to rapidly acquire 2D spectra which correlate 1H chemical shifts to the indirectly detected wideline MAS powder patterns of dipolar coupled hetero-nuclei. The D-HMQC pulse sequence enables broadband excitation of the wideline hetero-nuclear NMR spectrum and provides higher sensitivity by detecting the narrower and more sensitive 1H NMR signal. This approach is demonstrated for the rapid acquisition of 2D 1H detected 195Pt solid-state NMR spectra of cisplatin and transplatin and the 71Ga solid-state NMR spectrum of a self-assembled Ga coordination polymer of unconfirmed structure. This approach should be broadly applicable for the rapid acquisition of wideline MAS solid-state NMR spectra of moderately abundant NMR nuclei

Farmer Perception of Technology and its Impact on Technology Uptake: The Case of Fodder Legume in Central Kenya Highlands.

Technology adoption by farmers is crucial to increasing agricultural productivity hence meeting food and nutrition challenges in Africa. Economists investigating consumer demand have accumulated considerable evidence showing that consumers generally have subjective preferences for product attributes. However, when investigating adoption of new agricultural technologies, economists have lagged behind in analysing how farmers' (the consumer of agricultural technologies) subjective perceptions of technology characteristics affect their adoption decisions. Focusing on farmer perceptions of technologies may provide a better understanding of technology adoption since they deal with the technologies and probably perceive technologies differently from researchers and extension agents. The objective of this paper is to investigate farmers' perception of technology and its impact on adoption using a case study of legume forages in central Kenya highlands. Data from a random sample of 131 farm households in four districts in central Kenya was used. Using participatory techniques, four most important fodder legume attributes to farmers in their adoption decision were identified. These were then used in conjoint analysis. An ordered probit model was estimated to assess relative importance of each attribute to the farmer. A tobit model was also estimated to show the effect of farmers' perception of calliandra and desmodium on probability and intensity of adoption. Results showed that dry season tolerance and economy on land are most important characteristics of fodder legumes to the farmers. It was also found that Calliandra and desmodium were more relevant to the farmers in the area than other fodders. Farmers' perception of the two fodders had a significant impact on their adoption. Consequently, it was recommended that before introducing a technology in an area, it is necessary that the farmers' perception of the technology be analysed Conjoint analysis, ordered probit and tobit estimates, fodder legume adoption.Research and Development/Tech Change/Emerging Technologies,