Supplementary Pressure Research Articles

A bio-inspired strategy inspired by an elephant trunk to grip granules

Abstract The utilization of granular materials for transportation purposes has the potential to mitigate superfluous expenditures associated with the transportation process. Nevertheless, granular materials exhibit distinct flowability characteristics under specific circumstances, which can lead to challenges such as instability maintenance, intricate grasping tactics, and reduced efficiency throughout the grasping process. Hence, the grasping pattern of the trunk of the African elephant (Loxodonta Africana) was observed. Drawing inspiration from the aforementioned concept, this paper put forth a compelling approach centered around an air-powered flexible gripper platform comprising four distinct gripping stages. Our objective is to explore the correlation between the quantity of items and the supplementary pressure required to achieve successful gripping, while considering variations in object dimensions. This study has the potential to provide novel insights for enhancing the efficacy of granular material transportation through improved gripping mechanisms.

Effects of heat treatment on microstructure and mechanical properties of squeeze casting AlSi9Mg alloy flywheel housings formed with local supplementary pressure

Targeted squeeze casting components of the thick-walled locations with local supplementary pressure (LSP) can effectively realize the local forced shrinkage, which is very significant for the elimination of shrinkage defects. In this paper, the effects of solid solution temperature, solid solution time, aging temperature and aging time on AlSi9Mg aluminum alloy flywheel housing with large wall thickness difference and complex structure formed with LSP were investigated. The results showed that the LSP effectively refined the microstructure and accelerated the spheroidization process of eutectic silicon, which reduced the heat treatment holding time significantly. The twinning growth of silicon particles effectively hindered the dislocation motion, relieved the stress concentration, and improved the strength. The fishbone-like AlSiMnFe phase were passivated after heat treatment. Heat treatment can enhance the plasticity by breaking and spheroidizing the coarse needle-like eutectic silicon, and enhance the strength by refining and homogenizing the β" phase precipitated in the alloy. The optimum heat treatment parameters are solid solution at 540 °C for 210 min and aging at 175 °C for 480 min. Under the optimum heat treatment condition, the ultimate tensile strength, yield strength and elongation for the position with LSP reached 306.1 MPa, 237.5 MPa, 13.29 %.

Holistic View of Pandemic in Integrated Environment: New Variant of COVID Surge in the USA with Holistic Environment Participation in Creating Future More Aggressive Mutants

Planet Earth is a little one, and on one side it hosts the continents and on the opposite side is the Pacific Ocean, where the dry land represents 29%, from which 30% are deserts and 20% are mountains, while 50% is used for human activities. An integrated environment includes Earth and humans [1], as part of the Earth’s fauna, and any living creature from few nanometers up the very large ones, having in common pursue of life. The recent planetary SARS-Cov-2 pandemic [2] placed a special stress on the planet, and placed in the lime-light the dominant characteristics and moral values of humans, their incapability to identify a real threat, adapt and prevail. Due to coarse incompatibility of moral values of various nations, with real life values, many nations ended up politicizing the pandemic and having inappropriate preparedness and response, and as a consequence they recorded high losses in human lives and standard of lives. Earth registers a record high of death, of about 7 Million from which USA worth only 4% of Earth’s population contributed with an exceptionally tragic milestone of 1 Million deaths [3]. Due to inappropriate measures to stop the pandemic, the planet slipped into economic troubles as inflation and supply cycles disruption, that set a supplementary pressure to climate challenge, and for some with terrible moral values for which truth is their enemy, needed an escape goat to distract from the real economic and cultural problem and badly needed a new war, in an exacerbation of xenophobia, hypocrisy and misinformation [4]. This new calamity, has good chances of transforming into a nuclear war, where about 10,000 strikes of about 100 Mt-TNT might be applied to northern hemisphere [5]. In the present conditions COVID is embedded in the environment [6], with new variants due to pandemic as delta, O’micron and BA2, and few more, and from environment is given back to humans, and a new surge appeared in Europe with a delay of about 2 mo. from the elimination of all restrictions. This means that by April- May US will be infected again, with a new version escaping previously made vaccines. In the eventuality of a Nuclear War, ignoring the directly affected areas, the presence of heat and then cold, radioactive pollution, will trigger the gain of function of many passive, or dormant viruses, which will find a new ground of reproduction on the hoards affected by the exposure to nuclear warfare, and having handicapped immunity systems [7]. The survivors from the nuclear war will find difficult to survive to the pandemic with radiation enhanced novel viruses and functional structures.

Considerations on reducing fuel consumption and emissions by optimizing traffic control in congested urban areas

The balance between city development, as, for example, an increasing number of working places and emissions control, is a challenge in our days in the urban environment. All new developments in the urban area, either commercial, office or residential, will generate a specific demand for mobility. This new demand will put supplementary pressure on the urban transport system in the influence area. Therefore, approaching it from a macro to micro dimension using transport models would be a benefit for both, as optimizing the traffic control in main junctions in the area of the development will reduce the traffic congestion and delays. The paper deals with effects on reducing fuel consumption and emissions as an effect of optimization of traffic control in main junctions in the areas of new developments.

Research and method of air burst fracturing

At present, shale gas pressure fracturing volume development technology tends to be mature, shale gas backlog fracturing ends and enters the trial production stage. Due to the improper control of oil nozzle or its causes, the output drops sharply, or the drainage in the production process makes the funnel effect near the wellbore zone, resulting in the closure of the main fracture passage near the wellbore. However, the far-end complex sealing network structure produced by volume fracturing technology is still not fully closed, or secondary fractures occur in the absence of support for the original wellbore fractures or new complex fractures occur in the vicinity of the wellbore. The simple use of high-energy gas fracturing requires low cost, safety and simple and efficient characteristics, and the requirements for surface equipment are not too high. Existing methods mainly include well testing, sand washing by coiled tubing, gas lifting by coiled tubing, wellbore plugging removal, pumping and drainage by supplementary pressure well operator, etc. They can not fundamentally solve the need of closing or reopening new fractures in wellbore, and can not make new complex unclosed fractures near wellbore zone (without secondary fracturing). If the investment of surface equipment for secondary fracturing is similar to that of the first volume fracturing, and the investment is similar, the more complex situation will arise because of filtration and other reasons. At present, low concentration methane in air and wellbore is used to oxidize and exothermic to produce CO2 and H2O, and release energy at the same time. Temperature and pressure are the main means of energy in limited space. High energy gas formed after volume work can help to reopen the original fracture and form a new type of high energy gas fracturing method by means of air ignition and explosion, because the effect of high energy gas fracturing is not affected by stress, new cracks can be produced, and this crack can avoid overlapping with previous cracks. In particular, it can be pointed out that due to the improvement of thermal recovery of heavy oil and other means, the ground operation equipment has the commonality, and reasonable optimization of the construction plan can achieve the established purpose.

On the temporal evolution of particle production in f(T) gravity

The thermodynamical study of the universe allows particle production in modified [Formula: see text] ([Formula: see text] is the torsion scalar) theory of gravity within a flat FLRW framework for line element. The torsion scalar [Formula: see text] plays the same role as the Ricci scalar [Formula: see text] in the modified theories of gravity. We derived the [Formula: see text] gravity models by taking [Formula: see text] as the sum of [Formula: see text] and an arbitrary function of [Formula: see text] with three different arbitrary function. We observe that the particle production describes the accelerated expansion of the universe without a cosmological constant or any unknown “quintessence” component. Also, we discussed the supplementary pressure, particle number density and particle production rate for three cases.

Hydraulic resistance accompanying waterjet cutting

Introduction. Two-phase flow transmission is a complex process exposed to the influence of numerous factors. Its characteristics may depend on the physical properties of a flowing medium and on the properties of a pipeline, flow velocities, etc. A research into new types of hydraulic systems serves to identify the parameters that characterize the processes that accompany their transmission, especially if a multi-component flow is analyzed (a mix of water and abrasive particles). The mission of the research is to identify the value of hydraulic resistance coefficient in the course of transmission of a two-phase flow, or a mix of water and an abrasive. Materials and methods. A physics experiment, mathematical data processing methods, data description.
 Results. The co-authors have identified the hydraulic resistance coefficient value in the course of the mix transmission, as well as the parameters characterizing supplementary pressure losses in the course of the abrasive transmission. The experimental research enabled the co-authors to identify maximal water and mix application distances that reach 317 and 290 meters.
 Conclusions. The results, obtained by the co-authors, are the consequence of the pressure losses that occur in the course of mix transmission and the coefficients that characterize it. The flows considered in the article are used in the systems whose parameters are considerably different from those of traditional hydraulic engineering systems; therefore, any theoretical results obtained by the co-authors need experimental verification. Further, similar systems having different parameters must also be exposed to research to identify the relation between the pressure loss and the abrasive consumption rate and amount. The practical value of the research consists in the identification of maximal water and mix transmission and application distances providing that the operating parameters of the systems remain unchanged.

Supplementary pressure comparison from 10 MPa to 100 MPa in hydraulic media at gauge mode

The regional supplementary comparison EURAMET.M.P-S13 for pressure measurements in liquid media from 10 MPa to 100 MPa was piloted by the TÜBİTAK UME Pressure Laboratory, Turkey. The transfer standard was a digital pressure gauge, serial number 116321, manufactured by Paroscientific Inc. Eighteen laboratories participated in this comparison. Fourteen laboratories are from EURAMET region; namely UME, MKEH, BoM, DPM, DMDM, MBM, GUM, IMT, HMI/FSB-LPM, VSL, VTT MIKES, FORCE Technology, IMBIH, NSAI NML. VMC is from COOMET and QAF, EMI, SASO NMCC are from GULFMET region.Main textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Supplementary pressure comparison from (0.7 to 7) MPa in gas media at gauge mode

This report gives the results of a comparison of pressure standards of three National Metrology institutes in the range of 0.7 MPa to 7 MPa. This comparison was piloted by UME and was carried out from February 2017 to March 2019. This work is a part of the GULFMET project and is registered as a supplementary comparison GULFMET.M.P-S1. The transfer standard used was a digital pressure gauge, model 745-1K, serial number 114944, manufactured by Paroscientific Inc, with a resolution of 1 hPa. The reference values have been determined from the weighted mean of the deviations which is a measurement error of the test instrument reported by the participants for each specified pressure.Main textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Determination of peptide antibiotics in animal food by capillary electrochromatography coupled with laser induced fluorescence

A rapid and sensitive method was established for the analysis of peptide antibiotics (bacitracin, polymyxin B and colistin) in animal food by capillary electrochromatography (CEC) coupled with laser induced fluorescence (LIF) using 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) as fluorogenic reagent. Peptide antibiotics were derivatized by NBD-F in 50 mmol/L borate buffer (pH 7.5) for 45 min at 60℃. The fluorescence derivatives of peptide antibiotics were separated on a packed phenyl capillary column with a mobile phase consisting of acetonitrile-potassium phosphate (pH 5.0, 10 mmol/L) (55:45, v/v) at the flow rate of 0.02 mL/min. A supplementary pressure of 3.8 MPa and a separation voltage of -10 kV were applied. The limits of detection (LODs, S/N=3) were 5.0-10.0 ng/mL, which fulfilled the requirement of maximum residue limits for examined peptide antibiotics. The method was applied to detect peptide antibiotics in milk and feed stuffs. The spiked recoveries of the three peptide antibiotics were 72.9%-112.4%. The method shows some advantages on the simpler pretreatment and higher sensitivity, which can be of great benefit to the residual analysis of the veterinary drugs.

Quartz–coesite–stishovite relations in shocked metaquartzites from the Vredefort impact structure, South Africa

AbstractCoesite and stishovite are developed in shock veins within metaquartzites beyond a radius of ~30 km from the center of the 2.02 Ga Vredefort impact structure. This work focuses on deploying analytical field emission scanning electron microscopy, electron backscattered diffraction, and Raman spectrometry to better understand the temporal and spatial relations of these silica polymorphs. α‐Quartz in the host metaquartzites, away from shock veins, exhibits planar features, Brazil twins, and decorated planar deformation features, indicating a primary (bulk) shock loading of >5 < 35 GPa. Within the shock veins, coesite forms anhedral grains, ranging in size from 0.5 to 4 μm, with an average of 1.25 μm. It occurs in clasts, where it displays a distinct jigsaw texture, indicative of partial reversion to a less dense SiO2 phase, now represented by microcrystalline quartz. It is also developed in the matrix of the shock veins, where it is typically of smaller size (<1 μm). Stishovite occurs as euhedral acicular crystals, typically <0.5 μm wide and up to 15 μm in length, associated with clast–matrix or shock vein margin–matrix interfaces. In this context, the needles occur as radiating or subparallel clusters, which grow into/over both coesite and what is now microcrystalline quartz. Stishovite also occurs as more blebby, subhedral to anhedral grains in the vein matrix (typically <1 μm). We propose a model for the evolution of the veins (1) precursory frictional melting in a microfault (~1 mm wide) generates a molten matrix containing quartz clasts. This is followed by (2) arrival of the main shock front, which shocks to 35 GPa. This generates coesite in the clasts and in the matrix. (3) On initial shock release, the coesite partly reverts to a less dense SiO2 phase, which is now represented by microcrystalline quartz. (4) With continued release, stishovite forms euhedral needle clusters at solid–liquid interfaces and as anhedral crystals in the matrix. (5) With decreasing pressure–temperature, the matrix completes crystallization to yield a microcrystalline quasi‐igneous texture comprising quartz–coesite–stishovite–kyanite–biotite–alkali feldspar and accessory phases. It is possible that the shock vein represents the locus of a thermal spike within the bulk shock, in which case there is no requirement for additional pressure (i.e., the bulk shock was ≃35 GPa). However, if that pressure was not realized from the main shock, then supplementary pressure excursions within the vein would have been required. These could have taken the form of localized reverberations from wave trapping, or implosion processes, including pore collapse, phase change–initiated volume reduction, and melt cavitation.

Impact of Yoga on Blood Pressure and Quality of Life in Patients with Hypertension

Background: Medical treatment of hypertension is not always sufficient to achieve blood pressure control. Despite this, previous studies on supplementary therapies, such as yoga, are relatively few. The investigator evaluated the effects of yoga intervention on blood pressure and quality of life in patients in selected hospital diagnosed with hypertension. Methods: Adult patients (age 20–80 years) with diagnosed hypertension were identified at OPD of Meenakshi Medical College and Hospital. In total, 83 subjects with blood pressure values of 120–179/≤109 mmHg at baseline were enrolled. At baseline, the patients underwent standardized blood pressure measurement at the health care center and they completed a questionnaire on self-rated quality of life (WHOQOL). There were three groups: 1) Yoga class with investigator (n = 28); 2) Yoga at home (n = 28); and 3) a control group (n = 27). The participants were matched at the group level for systolic blood pressure. After 12 weeks of intervention, the assessments were performed again. At baseline a majority of the patients (92%) were on antihypertensive medication, and the patients were requested not to change their medication during the study. Results: The yoga class group showed improvement in blood pressure or self-rated quality of life, while in the yoga at home group there was a decline in diastolic blood pressure of 4.4 mmHg (p less tha 0.05) compared to the control group. Moreover, the yoga at home group showed significant improvement in self-rated quality of life compared to the control group (p less than 0.05). Conclusions: A short yoga program for the patient to practice at hospital seems to have an antihypertensive effect, as well as a positive effect on self-rated quality of life compared to controls. This implies that simple yoga exercises may be useful as a supplementary blood pressure therapy in addition to medical treatment.

Drop size distribution monitoring of oil-in-water emulsions in SMX+ static mixers: Effect of operating and geometrical conditions

Static mixers provide enhanced mixing via a motionless element inside a rigid pipe, and are widely used for continuous mixing and blending in industry. This study focuses on the emulsification of a silicon oil-in-water system stabilized by a surfactant through SMX+® static mixers involving no mass transfer between the two phases. The experiments covered a large domain of dispersed fraction from dilute conditions (5%vol.) up to concentrated ones (60%vol.) close to phase inversion and three different viscosities from 20 to 350mPa s with transitional or turbulent flow regimes. The number of static mixers was studied until a constant drop size distribution monitored at line with a video probe was obtained. With the considered flow rates, only the five first SMX+ elements were necessary to achieve a complete drop breakup and coalescence equilibrium, the following ones only causing a supplementary pressure drop. The influence of the number of SMX+ and energy dissipation rate was found to be of first order compared to the volume fraction or viscosity of the dispersed phase. According to the large amount of data, it was possible to establish a new form of a Middleman correlation dedicated to this type of mixer of new generation. The formula takes into account the number of static mixers besides other hydrodynamic and physicochemical parameters.

Particle creation in cosmology with varying speed of light

This paper investigates the behaviour of the particle creation in Einstein’s field equations with a variable speed of light and variable energy density in the context of open thermodynamical systems where the particle creation gives rise to a supplementary negative creation pressure in addition to the thermodynamic pressure. The dynamical behaviour of the cosmological models has been investigated.

Pressurized CEC with amperometric detection using mixed‐mode monolithic column for rapid analysis of chlorophenols and phenol

A simple analysis of chlorophenols (2-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, and pentachlorophenol) and phenol was accomplished by coupling a pressurized CEC with amperometric detection (AD). Efficient and reproducible separation of these compounds was achieved within 9 min on a capillary monolithic stationary phase bonded with octadecyl ligands and sulfonate groups, where the selectivity and the retention of analytes can be functionally controlled by optimizing experimental variables, including organic modifier content, mobile phase pH, ionic strength, working electrode potential, separation voltage, and supplementary pressure. A mixed-mode retention mechanism consisting of reverse-phase chromatographic partition, electrostatic repulsion, and electrophoresis is considered to play roles in the separation. The use of ACN-based media seems effectual in preventing the unfavorable irreversible adsorption on both wall and electrode, and offer higher sensitivity and less electrode fouling in AD of phenols. The LODs were in the range from 0.02 to 0.2 μg/mL with a wide linear dynamic range of 5000-fold, while the peak area precision ranged from 3.2 to 7.5%. The feasibility of using this method in real analysis was evaluated by recovery estimates and comparative experiment on spiked tap water samples. Good recoveries of 80-110% were achieved. Additionally, a paired t-test was used to correlate the two methods.

Rapid analysis of trace levels of flavins by pressurized capillary electrochromatography-laser induced fluorescence detection with sulfonated N-octadecyl methacrylate monolith

In this paper, pressurized capillary electrochromatography (pCEC) with laser induced fluorescence detection (LIF) was demonstrated as a viable approach for the separation and determination of trace flavins in human plasma, where flavins tend to be degraded ex vivo. Using a sulfonated N-octadecyl methacrylate monolithic column in isocratic pCEC separation, symmetrical peak shapes and rapid separation could be obtained in a weakly acidic mobile phase. Baseline separation of riboflavin, flavin mononucleotide and flavin adenine dinucleotide could be achieved within 4.5 min in a mobile phase containing 60% (v/v) acetonitrile and 40% (v/v) of 20 mmol L −1 phosphate buffer (pH 4.0), with −22 kV of applied voltage and 290 psi of supplementary pressure and 0.02 mL min −1 of flow rate. Based on a 473 nm laser diode double pumped solid state source, flavins could be determined by LIF with the detection limit (LOD) as low as 0.5 nmol L −1 (S/N = 3). The concentration ranges were 0.005–2 μmol L −1 for RF and FMN, and 0.02–40 μmol L −1 for FAD. Owing to the weakly acidic condition selected in this experiment, the high fluorescence quantum yields and good stability of flavins contributed to a preferable analysis. Combined with a simple clean-up procedure, this method has been proved to be effective for the rapid and selective analysis of trace levels of flavins in human plasma without sample preconcentration.

Off-Column Amperometric Detection for Pressurized Capillary Electrochromatography

A system enabling coupling of pressurized capillary electrochromatography (pCEC) with off-column amperometric detection (AD) is reported in which conduction of the current in pCEC was achieved through a cellulose acetate-coated porous polymer joint, and the effect of the high-voltage field applied to pCEC for AD was also eliminated. Effects of supplementary pressure on the porous polymer joint and the effects on AD of capillary columns of different i.d. were investigated. The performance of the pCEC–AD system with the porous polymer joint was evaluated with phenol and hydroquinone using sulfonated stearyl methacrylate monolithic columns. The separation efficiency of the column in pCEC–AD, using the proposed off-column detection with the cellulose acetate membrane joint, was comparable with that of pCEC–UV using on-column detection. Compared with end-column detection using a 50 μm i.d. capillary column without a joint, a higher signal-to-noise ratio was achieved, even using a 100 μm i.d. capillary column with a joint. Successful separation and detection of dopamine and epinephrine were also achieved by use of this system.

Analysis of phenolic xenoestrogens by pressurized CEC with amperometric detection

A new method, pressurized CEC with end-column amperometric detection using carbon paste electrode, has been developed for the separation and determination of five phenolic xenoestrogens in chicken eggs and milk powder samples. Efficient separation of five analytes was performed by pressurized CEC using a mobile phase consisting of 60% v/v ACN and 40% v/v Tris buffer (5 mmol/L, pH 8.0), +6 kV of applied voltage and 7.0 MPa of supplementary pressure. Detection limits of 50, 5, 2, 10 and 20 ng/mL for pentachlorophenol, bisphenol-A, 2,4-dichlorophenol, 4-tert-octylphenol and 4-nonylphenol, respectively, were achieved using carbon paste electrode as working electrode and +0.8 V as detection potential. Matrix solid phase dispersion extraction method had been employed during sample preparation procedure, and mean recoveries ranged from 79.2 to 102.6% at different concentrations of phenolic xenoestrogens for spiked egg and milk powder samples were obtained.

Separation and determination of structurally related free bile acids by pressurized capillary electrochromatography coupled to laser induced fluorescence detection

A sensitive pressurized capillary electrochromatography-laser induced fluorescence detection (pCEC-LIF) method has been developed for the simultaneous analysis of five structurally related free bile acids including cholic acid (CA) and lithocholic acid (LCA), as well as the stereoisomers of chenodeoxycholic acid (CDCA), deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA). 4-nitro-7-N-piperazino-2,1,3-benzoxadiazole (NBD-PZ) was used for the precolumn derivatization of non-chromogenic free bile acids to form strongly fluorescent adducts. Efficient separation of these derivatization products was performed within 17 min by isocratic elution pCEC on an octadecyl silica (ODS) packed capillary column, using a mobile phase consisting of acetonitrile and 10 mM CAPS buffer (pH 8.0) (60:40 v/v), 20 kV of applied voltage and 10.8 MPa of supplementary pressure. The derivatized bile acids could be determined by a LIF detector at an excitation wavelength of 473 nm and an emission wavelength of 530 nm, with detection limits (signal/noise = 3) down to 2 nmol L−1. Applicability of this pCEC-LIF method to the analysis of human serum samples was demonstrated. Accepted recoveries ranging between 94.8% and 109.7% for all analytes in spiked human serum samples were achieved. This method has potential for the trace analysis of physiologically important acidic analogs.

Quantification of domoic acid in shellfish tissues by pressurized capillary electrochromatography

A method was developed to quantify domoic acid (DA), the chemical responsible for amnesic shellfish poisoning (ASP), by pressurized CEC (pCEC). The effect of different experimental conditions on the separation of DA and matrix solutes, such as the content of ACN in mobile phase, pH and concentration of buffer, supplementary pressure and applied voltage, were investigated. Under the optimal conditions, the pCEC method separated DA from shellfish matrices within 6 min. By using supplementary pressure, bubble formation in the capillary column was completely suppressed. The method was repeatable, sufficient accurate and sensitive for rapid screening of DA in shell seafood.