Developing & Testing Components For More Reliable Linear Reciprocating Compression Of Hydrogen

LectureSouthwest Research Institute® (SwRI®), ACI Services, Inc. (ACI), and Libertine FPE Limited collaborated to design and build a Linear Motor Reciprocating Compressor (LMRC) via a DOE-funded project with ACI cost share. The advanced compression system utilizes a novel concept of driving a permanent magnet piston assembly inside a hermetically sealed compressor cylinder through electromagnetic windings. The LMRC design minimizes the mechanical part count and has no process gas leakage to atmosphere. The LMRC has no “rod,� rod packing, crankshaft, coupling, or separate motor/driver. In addition, the LMRC is able to improve the efficiency of the compression process by eliminating bearing losses and optimizing the piston speed profile to reduce fluid dynamic losses. The primary project objective was to meet the DOE goal of increasing the compression efficiency and reducing the cost of forecourt hydrogen compression; however, most of the associated technology developments can be applied to high-pressure natural gas, process gas, air, and other compressors. High pressures, electromagnetic fields, and a hydrogen environment (for the specific DOE vehicle refueling application) are the main design obstacles that had to be overcome to design a linear motor reciprocating compressor that can ultimately achieve a 12,700-psi final discharge pressure in the third stage. Manufacturing of the first stage LMRC (first of three stages) was completed and tested in early-to-mid 2020. Solid model images and a photo of the LMRC that was built and tested is presented in Figure 1. The first stage LMRC has design suction and discharge pressures of 290 and 1,035 psi, respectively. After a failure caused the testing to end prematurely, SwRI internal research and development (IR&D) funding was sought to rebuild the LMRC using the lessons-learned from the 2020 testing to improve some of the key components of the design. The key components that were the focus of the IR&D project are as follows: • Metal Coatings – Specifically, coatings for magnets. A new coating and process method was developed to protect magnets from hydrogen incursion. • Valve Design – Based on the identified design improvements, a new valve design with minimal leakage for hydrogen service was developed and built. • Motion Profile – Motion profile optimization efforts were performed with the rebuilt LMRC. Testing of the above-noted components of the LMRC was completed in early-to-mid 2022; therefore, test data is included in this lecture. In addition to those component developments, further advances in the hermetic actuator platform technology are expected to yield efficiency and durability benefits for subsequent phases of development ahead of commercial product launch. The paper will include discussions of design, manufacturing, and testing aspects of some of the individual components and of the entire LMRC. In addition to being highly relevant to the hydrogen gas economy, the LMRC is considered relevant and applicable to most gas compression industries

Moving from concept to control; use of phages for Campylobacter reduction

Poultry are a major source of Campylobacter with the organism having no impact on the bird. Irrespective of this situation, the important single source of campylobacteriosis is considered to be broiler meat (European Food Safety Authority 2016). The reported number of cases of campylobacteriosis in Australia in 2015 was 22,573 (Communicable Disease Intelligence 2019). Studies have suggested that a reduction in Campylobacter levels by greater than 2-log10 units would contribute to the reduction of the public health risk by more than 90% (European Food Safety Authority 2011). Overseas models have suggested that bacteriophage treatment has the greatest potential of all known/potential methods to reduce Campylobacter levels in the live chicken (Havelaar et al. 2007). Campylobacter naturally colonises the chicken gut, where it can reach high numbers and potentially contaminate the marketed product. A low number of organisms can cause human illness. This study is exploring a biocontrol option using bacteriophages (phages) to reduce Campylobacter numbers in chickens. Bacteriophages are viruses that infect and kill the target bacteria. These specific, Campylobacter-killing phages occur naturally in farm chickens, where they are already in a ‘predator–prey relationship’ with Campylobacter. The aim of this study is to better the outcome of this natural phenomenon. The study builds upon data from previous studies to progress the option of using Campylobacter bacteriophages to control Campylobacter levels in poultry. The report is targeted at the Australian Poultry Industry, those with a role of food-safety at an industry level and also have a regulatory role

Community seroprevalence of SARS-CoV-2 in children and adolescents in England, 2019–2021

Objective: To understand community seroprevalence of SARS-CoV-2 in children and adolescents. This is vital to understanding the susceptibility of this cohort to COVID-19 and to inform public health policy for disease control such as immunisation. Design: We conducted a community-based cross-sectional seroprevalence study in participants aged 0–18 years old recruiting from seven regions in England between October 2019 and June 2021 and collecting extensive demographic and symptom data. Serum samples were tested for antibodies against SARS-CoV-2 spike and nucleocapsid proteins using Roche assays processed at UK Health Security Agency laboratories. Prevalence estimates were calculated for six time periods and were standardised by age group, ethnicity and National Health Service region. Results: Post-first wave (June–August 2020), the (anti-spike IgG) adjusted seroprevalence was 5.2%, varying from 0.9% (participants 10–14 years old) to 9.5% (participants 5–9 years old). By April–June 2021, this had increased to 19.9%, varying from 13.9% (participants 0–4 years old) to 32.7% (participants 15–18 years old). Minority ethnic groups had higher risk of SARS-CoV-2 seropositivity than white participants (OR 1.4, 95% CI 1.0 to 2.0), after adjusting for sex, age, region, time period, deprivation and urban/rural geography. In children <10 years, there were no symptoms or symptom clusters that reliably predicted seropositivity. Overall, 48% of seropositive participants with complete questionnaire data recalled no symptoms between February 2020 and their study visit. Conclusions: Approximately one-third of participants aged 15–18 years old had evidence of antibodies against SARS-CoV-2 prior to the introduction of widespread vaccination. These data demonstrate that ethnic background is independently associated with risk of SARS-CoV-2 infection in children. Trial registration number: NCT04061382

Serum HCoV-spike specific antibodies do not protect against subsequent SARS-CoV-2 infection in children and adolescents

SARS-CoV-2 infections in children are generally asymptomatic or mild and rarely progress to severe disease and hospitalization. Why this is so remains unclear. Here we explore the potential for protection due to pre-existing cross-reactive seasonal coronavirus antibodies and compare the rate of antibody decline for nucleocapsid and spike protein in serum and oral fluid against SARS-CoV-2 within the pediatric population. No differences in seasonal coronaviruses antibody concentrations were found at baseline between cases and controls, suggesting no protective effect from pre-existing immunity against seasonal coronaviruses. Antibodies against seasonal betacoronaviruses were boosted in response to SARS-CoV-2 infection. In serum, anti-nucleocapsid antibodies fell below the threshold of positivity more quickly than anti-spike protein antibodies. These findings add to our understanding of protection against infection with SARS-CoV-2 within the pediatric population, which is important when considering pediatric SARS-CoV-2 immunization policies

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good