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Transmission loss analysis of thick perforated plates for valve contained pipelines

Valve contained pipelines have witnessed a great growth and there exists a lot of noise caused by valves. Thick perforated plates are especially used is valve contained pipelines for the noise control, but there are limited literatures about its noise control performances under different structural parameter of thick perforated plates, which limits its popularization and application. In this paper

Limit bending moment for pipes with two circumferential flaws under combined internal pressure and bending

By assuming the neutral axis is perpendicular to the bending plane, this paper presents a general analytical solution to predict the limit bending moment for pipes with two inner surface circumferential flaws under combined internal pressure and bending moment. The circumferential stress caused by internal pressure is taken into account through Mises yield criterion. Based on the general solution,

Numerical analysis of flow and temperature characteristics in a high multi-stage pressure reducing valve for hydrogen refueling station

Hydrogen refueling station is one of the most important parts for the hydrogen energy utilization. In this paper, a novel high multi-stage pressure reducing valve (HMSPRV) is proposed, which can be used for hydrogen stable decompression in hydrogen refueling station. In HMSPRV, the inner and outer porous shrouded valve core is used to replace piston valve core to achieve the first-stage throttling

CFD analysis on the dynamic flow characteristics of the pilot-control globe valve

The pilot-control globe valve (PCGV) is a new kind valve with simple structures and low driving energy consumption. It can utilize the pressure difference before and after the valve to control the action of the valve core. However, systematic theoretical research and numerical analysis are deficient at present. In this paper, the mathematical model of PCGV is established and Computational Fluid Dy

Energy consumption prediction of university buildings in China and strategies for energy efficiency management

In 2007, Chinese Ministry of Education (MOE) and Ministry of Housing & Urban-Rural Development (MOHURD) carried out the Campus Resource Conservation Actions, in order to take full use of resources and to improve the energy efficiency. However, due to the large amounts of universities, the total energy consumption and the energy efficiency situation have no objective statistics. Taking modeling

Transient simulation of valve core movement of pilot-control globe valve in vertical pipelines

A novel pilot-control globe valve, which can be used in vertical pipelines with a lower driving energy consumption, is proposed. A governing equation for valve core motion is obtained through a theoretical analysis of the forces applied on the valve core. A 3D simulation of valve core motion is conducted in Fluent by using User Defined Function (UDF) to involve different spring stiffness, steady s

Numerical simulation of flow-induced noise in high pressure reducing valve

The main objective of this paper is to study the characteristics of flow-induced noise in high pressure reducing valve (HPRV) and to provide some guidance for noise control. Based on computational fluid dynamics (CFD), numerical method was used to compute flow field. Ffowcs Williams and Hawkings Model was applied to obtain acoustic signals. The unsteady flow field shows that noise sources are loca

Sialic Acid 4-N-Piperazine and Piperidine Derivatives Bind with High Affinity to the P. mirabilis Sialic Acid Sodium Solute Symporter

In search for novel antibacterial compounds, bacterial sialic acid uptake inhibition represents a promising strategy. Sialic acid plays a critical role for growth and colonisation of several pathogenic bacteria, and its uptake inhibition in bacteria was recently demonstrated to be a viable strategy by targeting the SiaT sodium solute symporters from Proteus mirabilis and Staphylococcus aureus. Her

A Checklist with Three New Species and Two New Country Records of Begonia from Dibang Valley, Arunachal Pradesh, India

A synoptical treatment of the Begonia flora of the Dibang Valley in eastern Arunachal Pradesh, India is provided, along with the descriptions of three new species. In total, eight species of Begonia are recognized as occurring in the area, of which B. atrofusca, B. lorentzonii and B. rushforthii are new to science, while B. acetosella var. hirtifolia and and B. pseudoheydei are new records for Ind

Reduced risk of serious pneumococcal infections up to 10 years after a dose of pneumococcal conjugate vaccine in established arthritis.

Background: To examine rates of serious pneumococcal infections up to 10 years after vaccination with 7-valent conjugated pneumococcal vaccine (PCV7) in patients with arthritis compared to non-vaccinated arthritis patients.Methods: In total, 595 adult arthritis patients (rheumatoid arthritis; RA = 342, 80 % women and spondylarthropathy; SpA = 253, 45 % women) received one dose of PCV7. Mean age/di

Biocompatible non-leachable antimicrobial polymers with a nonionic hyperbranched backbone and phenolic terminal units

This work aimed to develop biocompatible non-leachable antimicrobial polymers without ionic structures. A series of nonionic hyperbranched polymers (HBPs) with an isatin-based backbone and phenolic terminal units were synthesized and characterized. The molecular structures and thermal properties of the obtained HBPs were characterized by SEC, NMR, FTIR, TGA and DSC analyses. Disk diffusion assay r

The Use and Abuse of Normative Ethics for Moral Machines

How do we develop artificial intelligence (AI) systems that adhere to the norms and values of our human practices? Is it a promising idea to develop systems based on the principles of normative frameworks such as consequentialism, deontology, or virtue ethics? According to many researchers in machine ethics – a subfield exploring the prospects of constructing moral machines – the answer is yes. InHow do we develop artificial intelligence (AI) systems that adhere to the norms and values of our human practices? Is it a promising idea to develop systems based on the principles of normative frameworks such as consequentialism, deontology, or virtue ethics? According to many researchers in machine ethics – a subfield exploring the prospects of constructing moral machines – the answer is yes. In

Quantifying the impact of winter warming on the Arctic carbon cycle

The Arctic has undergone extreme changes during the last decades and is warming over twice the global average. There has been increasing interest in understanding how warming and changes in snow and rainfall will affect high-latitude ecosystems. Although observational studies highlight the importance of cold-season carbon fluxes on the annual carbon balance, models, in general, cannot realisticallThe Arctic has undergone extreme changes during the last decades and is warming over twice the global average. There has been increasing interest in understanding how warming and changes in snow and rainfall will affect high-latitude ecosystems. Although observational studies highlight the importance of cold-season carbon fluxes on the annual carbon balance, models, in general, cannot realisticall

Design and characterization of matrix metalloproteinase-responsive hydrogels for the treatment of inflammatory skin diseases

Enzyme-responsive hydrogels, formed by step growth photopolymerization of biscysteine peptide linkers with alkene functionalized polyethylene glycol, provide interesting opportunities as biomaterials and drug delivery systems. In this study, we developed stimuli-responsive, specific, and cytocompatible hydrogels for delivery of anti-inflammatory drugs for the treatment of inflammatory skin disease

Incidence and burden of illness at the Tokyo 2020 Paralympic Games held during the COVID-19 pandemic : a prospective cohort study of 66 045 athlete days

Objective To describe the incidence and burden of illness at the Tokyo 2020 Paralympic Games, which was organised with strict COVID-19 countermeasures. Methods Daily illnesses were recorded via the web-based injury and illness surveillance system (teams with their own medical staff; n=81), and local polyclinic services (teams without their own medical staff; n=81). Illness proportion, incidence an

Characterization of high Arabinoxylan oat lines identified from a mutagenized oat population

Oat (Avena sativa) is a nutritionally important cereal crop that is rich in health-promoting dietary fibers, favorable proteins and polar lipids. In this work, ca. 500 random lines of a mutagenized oat population of high genetic variation were screened for arabinoxylan (AX) content. This identified lines with up to 60% higher AX levels in flour from whole seed and up to 100% higher in flour from d

Single-Standard Quantification Strategy for Lignin Dimers by Supercritical Fluid Chromatography with Charged Aerosol Detection

The increased interest in utilizing lignin as a feedstock to produce various aromatic compounds requires advanced chemical analysis methods to provide qualitative and quantitative characterization of lignin samples along different technology streamlines. However, due to the lack of commercially available chemical standards, routine quantification of industrially relevant lignin oligomers in comple

Cosolvent Dimethyl Sulfoxide Influences Protein-Ligand Binding Kinetics via Solvent Viscosity Effects : Revealing the Success Rate of Complex Formation Following Diffusive Protein-Ligand Encounter

Protein-ligand-exchange kinetics determines the duration of biochemical signals and consequently plays an important role in drug design. Binding studies commonly require solubilization of designed ligands in solvents such as dimethyl sulfoxide (DMSO), resulting in residual amounts of DMSO following titration of solubilized ligands into aqueous protein samples. Therefore, it is critical to establis

The effects of station density in geostatistical prediction of air temperatures in Sweden : A comparison of two interpolation techniques

High fidelity gridded temperature datasets are difficult to obtain for areas with sparse coverage of meteorological stations given that sparsity of stations is known to introduce uncertainty in the interpolation of climatic variables generally. Inspired by their potential for optimal results especially for small sample datasets, we assessed and compared the accuracy of interpolation results of Emp

Nöden har ingen lag. Om demokratins överlevnad i en ’akut nödsituation’ : En reflektion över Sverige 2015

Allt våldsammare deportationer. Fler oskyldiga människor i fängsligt förvar. Fler svårt sjuka barn som skickas till länder där det är högst osäkert om de kan få vård. Ett stigande antal föräldrar som tar med sig sina barn på sjöodugliga båtar över medelhavet för att undvika mångårig separation. En växande mängd ungdomar som lever ett liv i papperslöshetens skuggsamhälle. Detta är några sannolika f