Quiescent System Research Articles

X-Ray Spectroscopy of the Dwarf Nova Z Chamaeleontis in Quiescence and Outburst Using the XMM-Newton Observatory

We present X-ray spectroscopy of the SU UMa–type dwarf nova Z Chamaeleontis using the European Photon Imaging Camera and reflection grating spectrometer (RGS) instruments on board the XMM-Newton observatory. The quiescent system can be modeled by collisional equilibrium (CIE) or nonequilibrium plasma models, yielding a kT of 8.2–13.0 keV at a luminosity of (5.0–6.0) × 1030 erg s−1. The spectra yield better χν2 using partially covering absorbers of cold and/or photoionized nature. The ionized absorber has an equivalent N H = (3.4–5.9) × 1022 cm−2 and a log(ξ) = 3.5–3.7 with a (50–60)% covering fraction when the VNEI model (XSPEC) is used. The line diagnosis in quiescence shows no resonance lines, with only the forbidden lines of Ne, Mg, and Si detected. The H-like C, O, Ne, and Mg are detected. The strongest line is O viii, with (2.7–4.6) × 10−14 erg s−1 cm−2. The quiescent X-ray-emitting plasma is not collisional and not in ionization equilibrium, which is consistent with hot ADAF-like accretion flows. The line diagnosis in the outburst shows He-like O and Ne, with intercombination lines being the strongest, along with weaker resonance lines. This indicates the plasma is more collisional and denser, but not yet in CIE, revealing ionization timescales of (0.97–1.4) × 1011 s cm−3. The R ratios in the outburst yield electron densities of (7–90) × 1011 cm−3 and the G ratios yield electron temperatures of (2–3) × 106 K. The outburst luminosity is (1.4–2.5) × 1030 erg s−1. The flow is inhomogeneous in density. All detected lines are narrow, with widths limited by the resolution of RGS, yielding Keplerian rotational velocities <1000 km s−1. This is too low for boundary layers, consistent with the nature of ADAF-like hot flows.

On the modes of nanosecond pulsed plasmas for combustion ignition of quiescent CH4-air mixtures

The effect of transient plasma modes on ignition kernel development are discussed here for a quiescent CH4-air combustion model system. A 10 ns high-voltage pulse was applied to a pin-to-pin electrode in lean fuel-air mixtures at room temperature and atmospheric pressure. High-impedance streamer, transient spark and low-impedance spark discharges were identified based on pulse waveforms of voltage and current. A sustained ignition kernel expansion was observed when the plasma discharge transitioned into a transient spark or spark discharge. The minimum ignition energy was obtained at the transient spark mode, which has less than a third of the energy or Coulomb transfer compared to the low-impedance spark. Employing repetitive 10-pulse sequence at 10 kHz, the lean-fuel limit was extended from an equivalence ratio of 0.6 for the single pulse ignition to 0.5. The use of repetitive pulses also allowed streamer breakdown or spark initiation to occur at a lower voltage.

Spectroscopic Confirmation of an Ultra-Massive Galaxy in a Protocluster at z ∼ 4.9

We present spectroscopic confirmation of an ultra-massive galaxy (UMG) with log(M⋆/M⊙)=10.98±0.07 at zspec=4.8947 in the Extended Groth Strip (EGS), based on deep observations of Ly α emission with Keck/DEIMOS. The ultra-massive galaxy (UMG-28740) is the most massive member in one of the most significant overdensities in the EGS, with four additional photometric members with log(M⋆/M⊙)&gt;10.5 within Rproj∼1 cMpc. Spectral energy distribution (SED) fitting using a large suite of star formation histories and two sets of high-quality photometry from ground- and space-based facilities consistently estimates the mass of this object to be log(M⋆/M⊙)∼11 with a small standard deviation between measurements ( σ=0.07). While the best-fit SED models agree on stellar mass, we find discrepancies in the estimated star formation rate for UMG-28740, resulting in either a star-forming or quiescent system. 𝐽𝑊𝑆𝑇/NIRCam photometry of UMG-28740 strongly favors a quiescent scenario, demonstrating the need for high-quality mid-IR observations. Assuming the galaxy to be quiescent, UMG-28740 formed the bulk of its stars at z&gt;10 and is quenching at z∼8, resulting in a high star formation efficiency at high redshift ( ϵ∼0.2 at z∼5 and ϵ≳1 at z≳8). As the most massive galaxy in its protocluster environment, UMG-28740 is a unique example of the impossibly early galaxy problem.

Exploiting the Electrical Nature of Biofilms for Long-Term Monitoring of Quiescent Aquatic Environments via Open-Circuit Microbial Potentiometric Sensors: Evidence of Long-Distance Electrical Signaling

This study was based on the hypothesis that spatial–temporal characterization of contaminant-affected redox gradients in a quiescent system could be measured by microbial potentiometric sensor (MPS) arrays incorporated in large, natural biofilm networks. Two experimental chambers, each containing at least 48 equidistantly located MPS electrodes, were fabricated to examine reproducibility of the patterns. The MPS electrodes were exposed to biofilm growth conditions by introducing high dissolved organic carbon (DOC) and dechlorinated tap water at the bottom of the experimental chamber; and the spatial–temporal changes in the MPS array signals were recorded, which showed that signal trends were correlated to the induced changes in DOC. The results indicated that MPS arrays measured the spatial–temporal changes in the aqueous solution caused by an influx of carbon rich water, which could not be detected by conventional oxidation-reduction potential (ORP) electrodes. Interestingly, the experiments conducted over long time periods revealed unusual behaviors like electrical signaling and possible potentiometrically driven communication within the biofilm. These observed behaviors suggest that biofilms may create a large network through which communication signals can be generated and propagated by inducing changes in electric potentials similar to a sophisticated electronic device.

Near-Zero Quiescent Power Sound Wake-Up and Identification System Based on a Triboelectric Nanogenerator.

Sound monitoring has been widely used in the field of the Internet of Things (IoT), in which the sensors are mainly powered by batteries with high power consumption and limited life. Here, a near-zero quiescent power sound wake-up and identification system based on a triboelectric nanogenerator (TENG) is proposed, in which the sound TENG (S-TENG) is used for ambient sound energy harvesting and system activation. Once the sound intensity is higher than 65 dB, the converted and stored electric energy by the S-TENG can wake up the system within 0.5 s. By integrating a deep learning technique, the system is used for identifying sound sources, such as drilling, child playing, dog barking, and street music. In the active mode, the sound signals are recorded by a microelectromechanical systems (MEMS) microphone and then sent to a remote computer for sound recognition through a wireless transmitter within 2.8 s. In the standby mode, the ambient sound is not enough to wake up the system, and the quiescent power consumption is only 55 nW. This work provides a triboelectric sensor-based ultralow quiescent power sound wake-up system, which has shown excellent application prospects in smart homes, unmanned monitoring, and the Internet of Things.

Can Radiotherapy Empower the Host Immune System to Counterattack Neoplastic Cells? A Systematic Review on Tumor Microenvironment Radiomodulation.

Despite the rising evidence in favor of immunotherapy (IT), the treatment of oncological patients affected by so-called “cold tumors” still represents an open issue. Cold tumors are characterized by an immunosuppressive (so-called cold) tumor microenvironment (TME), which favors host immune system suppression, cancer immune-escape, and a worse response to IT. However, the TME is not a static element, but dynamically mutates and can be changed. Radiotherapy (RT) can modulate a cold microenvironment, rendering it better at tumor killing by priming the quiescent host immune system, with a consequent increase in immunotherapy response. The combination of TME radiomodulation and IT could therefore be a strategy for those patients affected by cold tumors, with limited or no response to IT. Thus, this review aims to provide an easy, rapid, and practical overview of how RT could convert the cold TME and why cold tumor radiomodulation could represent an interesting strategy in combination with IT.

Endothelial EphrinB2 Regulates Sunitinib Therapy Response in Murine Glioma.

Vascular guidance is critical in developmental vasculogenesis and pathological angiogenesis. Brain tumors are strongly vascularized, and antiangiogenic therapy was anticipated to exhibit a strong anti-tumor effect in this tumor type. However, vascular endothelial growth factor A (VEGFA) specific inhibition had no significant impact in clinical practice of gliomas. More research is needed to understand the failure of this therapeutic approach. EphrinB2 has been found to directly interact with vascular endothelial growth factor receptor 2 (VEGFR2) and regulate its activity. Here we analyzed the expression of ephrinB2 and EphB4 in human glioma, we observed vascular localization of ephrinB2 in physiology and pathology and found a significant survival reduction in patients with elevated ephrinB2 tumor expression. Induced endothelial specific depletion of ephrinB2 in the adult mouse (efnb2i∆EC) had no effect on the quiescent vascular system of the brain. However, we found glioma growth and perfusion altered in efnb2i∆EC animals similar to the effects observed with antiangiogenic therapy. No additional anti-tumor effect was observed in efnb2i∆EC animals treated with antiangiogenic therapy. Our data indicate that ephrinB2 and VEGFR2 converge on the same pathway and intervention with either molecule results in a reduction in angiogenesis.

Superabsorbent polymer for improved CO2 hydrate formation under a quiescent system

The hydrate formation rate and conversion yield are essential factors for hydrate-based gas storage and accordingly various thermodynamic and kinetic promoters have been extensively investigated. However, for hydrate-based CO2 capture, carbonate ions induced from dissolved CO2 in water hinder the performance of kinetic promoters (e.g., sodium dodecyl sulfate (SDS)). In this work, we introduce a superabsorbent polymer (SAP) matrix that provides an extremely high interfacial area between a sorbed tetrahydrofuran (THF) solution and gaseous CO2. The SAP enhanced the formation rate of binary THF-CO2 hydrate, despite the absence of mechanical agitation. We varied the concentration of THF, temperature, reactor volume, and the ratio of solution to the reactor for a systematic study and explored their effects on the CO2 storage capacity and the induction time. We observed that highly concentrated THF and a larger reactor with a high gas-liquid contact area enhanced the CO2 storage capacity and formation rate. Raman and PXRD spectroscopic analyses were employed to investigate the guest distribution and crystalline structure of the THF-CO2 hydrates synthesized under various conditions. All the binary hydrates were structure-II (sII) hydrates, and there was no pure structure-I (sI) CO2 hydrate. Based on the spectroscopic results, we developed a theoretical model that could calculate the amount of enclathrated CO2 and dissolved CO2 in liquid phases separately. This work reveals that SAP has excellent potential for rapid CO2 capture in hydrate media with a high water-to-hydrate conversion ratio.

Tuning chemotactic and diffusiophoretic spreading via hydrodynamic flows.

The transport of microorganisms by chemotaxis is described by the same "log-sensing" response as colloids undergoing diffusiophoresis, despite their different mechanistic origins. We employ a recently-developed macrotransport theory to analyze the advective-diffusive transport of a chemotactic or diffusiophoretic colloidal species (both referred to as "colloids") in a circular tube under a steady pressure-driven flow (referred to as hydrodynamic flow) and transient solute gradient. First, we derive an exact solution to the log-sensing chemotactic/diffusiophoretic macrotransport equation. We demonstrate that a strong hydrodynamic flow can reduce spreading of solute-repelled colloids, by eliminating super-diffusion which occurs in an otherwise quiescent system. In contrast, hydrodynamic flows always enhance spreading of solute-attracted colloids. Second, we generalize the exact solution to show that the above tunable spreading phenomena by hydrodynamic flows persist quantitatively for decaying colloids, as may occur with cell death, for example. Third, we examine the spreading of chemotactic colloids by employing a more general model that captures a hallmark of chemotaxis, that log-sensing occurs only over a finite range of solute concentration. Apart from demonstrating for the first time the generality of the macrotransport theory to incorporate an arbitrary chemotactic flow model, we reveal via numerical solutions new regimes of anomalous spreading, which match qualitatively with experiments and are tunable by hydrodynamic flows. The results presented here could be employed to tailor chemotactic/diffusiophoretic colloid transport using hydrodynamic flows, which are central to applications such as oil recovery and bioremediation of aquifers.

Numerical modeling of adjacent bubble interactions under the influence of induced vibrations in liquid pool using lattice Boltzmann method (LBM)

This paper reports our numerical investigation on the bubble dynamics of two adjacent bubbles formed on the heated surface as the liquid pool is subjected to induced vibrations caused by oscillating solid bodies in periodic motion. The modeling involves 2D simulations of the entire ebullition cycle comprising of bubble nucleation, growth, coalescence, and departure by employing a combination of multiple relaxation time based lattice Boltzmann method with the finite difference method based thermal model. The numerical results throw insight into the different processes pertaining to bubble growth in the two systems, viz., the quiescent system (QS) and the system with oscillating solid bodies (OSBS). These include the bubble growth rate, vapor bridge formation, subsequent coalescence, and movement of three-phase contact lines. It is observed that the induced vibrations in the liquid pool leads to earlier nucleation and growth of the bubbles, and higher bubble departure frequency (f∗) due to additional forces acting on the bubble, which at one instance helps the two adjacent bubbles to coalesce and at the following instance pulls the coalesced bubble off the solid surface. A force balance analysis is presented to explain the evolution of the adjacent bubbles and their interactions. A sensitivity study is conducted to investigate the effects of unequal sizes of nucleation sites, unequal surface superheat (Ja), and distance between the nucleation sites. In all these cases, multiple bubbles are seen to form on the heated elements, which subsequently coalesce with each other and depart in a single ebullition cycle in OSBS, whereas only two initially formed bubbles are seen to merge and depart in a single ebullition cycle in QS. Subsequently, a sensitivity study is conducted to investigate the effects of surface wettability, and it is found that for a given surface superheat (Ja) and configuration of nucleation sites, f* reduces after a threshold value of wetting angle (θ∗) in QS while it reaches a maximum in OSBS before coming down. It is further observed that if the hydrophobicity of the surface is increased from θ* = 1.0 to 1.1 in OSBS, f∗ remains high until a threshold Ja, beyond which it reduces drastically due to a higher rate of bubble generation compared to detachment.

The influence of oriented external electric field on lipase catalyzed triglyceride hydrolysis

The use of microbial lipases for the hydrolysis of natural oils such as triglyceride esters is a green alternative to conventional processes to produce high value-added chemicals. Biocatalysis using lipases in aqueous solutions is limited often by instabilities, slow kinetics due to mass transfer limitations, and by challenges of economic lipase recycling. Prior work has shown that mass transfer rates and reaction rates can be intensified by increasing interfacial area using electrostatic spray reactors. However, the possible effect of oriented external electrical field on the lipase catalytic activity has hitherto not been considered. In this study, the performance of microbial lipase derived from Candida rugosa in aqueous solutions was analyzed in the presence of a steady DC externally applied electrical voltage. The reaction was conducted in three different batch type reactors, quiescent (fixed interface), stirred tank, and tubular flow system. In each of the three reactor systems it was concluded that the oriented external electrical field has a positive effect on reaction independently of interfacial area. Further studies conducted using reverse polarity, increased electrode distance and for an immobilized lipase system have shown that lipase undergoes conformational changes due to an oriented external electrical field is the main driving mechanism for this enhanced performance.

Promotion of CH4 hydrate generation by various surfactants in quiescent system for renewable energy application

Biogas can be used as a supplement to the consumption gap of natural gas, a propellant for low-carbon and circular economy, as well as an important component in energy security. The storage and transportation of biogas by hydrate method is widely concerned at home and abroad. The main component of biogas is methane. In this paper, two kinds of surfactants, fatty alcohol polyoxyethylene ether (AEO) and fatty alcohol polyoxyethylene ether sodium sulfate (AES), were selected to study the effects of their types and concentrations on the induction time and formation rate of CH4 hydrate. The results showed that the optimum mass concentrations of AEO and AES in hydration system were 2.5% and 0.1%, respectively, and the induction time of CH4 hydrate formation was 63min and 64min, respectively. AEO is beneficial to the formation of CH4 hydrate nuclei, and its promoting mechanism is micelle theory; while AES promotion mechanism is mainly adsorption. The research results are of great significance for the development of rural clean and renewable energy, the prevention of agricultural source pollution, and the consolidation of ecological environment construction.

A detailed morphology investigation on the effects of mixed anionic and nonionic surfactants on methane hydrate formation and dissociation

Foam generation from the presence of sodium dodecyl sulfate (SDS) as a kinetic promoter in methane hydrate formation can be potentially reduced by using mixed surfactants. Mixtures of SDS with nonionic surfactants were proposed to solve this problem. Polyoxyethylene (n) lauryl ether (EO3 and EO5) and alkyl poly glycol ether (APG) were chosen to mix with SDS in different concentrations at 8 MPa and 4 °C in the quiescent system for both kinetics and morphology studies. The result showed that the addition of EO3 resulted in the slight increase for the induction time but no change in the formation rate. Adding EO5 showed the stochastic phenomenon on hydrate formation kinetics. In the presence of APG, the induction time increased up to ten times and lowered the hydrate formation rate compared to only 0.25 wt% SDS. The methane uptakes were about the same with all conditions. The morphology showed similar hydrate formation and dissociation patterns with all investigated solutions. Interestingly, the mixture of nonionic surfactants with SDS decreased the foam formation compared with the system with only SDS. The addition EO3 showed the gradual decrease in the foam height with the higher concentration of EO3. Adding the highest EO5 concentration showed the optimum foam reduction compared with all conditions. Moreover, the presence of APG showed the similar effects of foam reduction with EO5.

Rhamonolipids produced by Pseudomonas aeruginosa promotes methane hydrates formation in fixed bed silica gel medium

Natural gas hydrates are seen as an alternative future energy source. They have also been valued for their carbon dioxide capturing capability, gas separation, desalination, natural gas storage and transportation. Developing economical and viable gas hydrate based technology is one of the most promising research areas of present decade. Successful commercialization of gas hydrate based technology is often curtailed due to slow formation rate. The present study evaluates biosurfactant as a kinetic promoter of methane hydrates formation in a fixed bed C type silica gel medium. Biosurfactant was produced by growing Pseudomonas aeruginosa strain A11 in glycerol supplemented mineral salt medium. Biosurfactant characterization with FTIR, NMR and MALDI-TOF spectroscopy reveled it to be a glycolipids type biosurfactant namely rhamnolipids. Saturating C type silica gel with of 100 ppm rhamnolipids solution enhanced the rate of methane hydrates formation by reducing the induction time. Mole of methane consumed and percentage of water to hydrate conversion was observed to be more in 1000 ppm rhamnolipids saturated C type silica gel as compared to quiescent water system and water saturated silica gel system. Overall results suggest that rhamonolipids produced by strain A11 in combination with silica gel can be utilized as environmentally safe kinetic promoter for methane hydrate formation.

COVD-02. ADAPTING RNA-NANOPARTICLE VACCINES FROM GLIOBLASTOMA TO SARS-COV-2

BACKGROUNDGlioblastoma (GBM) can be an effective teacher in the war on COVID-19, as an operative vaccine for either must elicit near-immediate protective responses that overcomes disease heterogeneity and immune suppression. Current prophylactic strategies against COVID-19 utilize mRNA vaccines targeting small fragments of the SARS-CoV-2 genome, but these may not induce robust T cell responses or elicit immunity quickly enough.OBJECTIVEWe sought to adapt an FDA-IND approved mRNA vaccine in GBM against COVID-19 for: 1) activation of near immediate immune responses, 2) targeting of full-length SARS-CoV-2 structural proteins, and 3) induction of bidirectional (B and T cell) adaptive immunity.METHODSWe utilized a novel engineering design that layers mRNA into a lipid-nanoparticle (NP) shell (much like an onion); this allows greater packaging of mRNA per particle to quickly boost innate/adaptive immune responses against full-length glioblastoma antigens or SARS-CoV-2 structural proteins.RESULTSIn small and large animal models, RNA-NPs safely mimic viremia activating the quiescent immune system in only a few hours for induction of protective immunity against its mRNA payload. RNA-NPs activate dendritic cells (DCs), upregulate critical innate gene signatures, and induce antigen-specific cellular and humoral immunity. We found that mice receiving SARS-CoV-2 spike RNA-NPs had more effector T cells after vaccination with significant memory recall expansion after in vitro re-stimulation with overlapping SARS-CoV-2 spike peptide mix. We also found increased release of MIP-1-alpha (i.e. CCL3) previously shown by our group (Mitchell et al. Nature 2015) to be responsible for Th1 mediated memory recall to infectious vaccine antigens in GBM patients.CONCLUSIONSARS-CoV-2 RNA-NPs elicit memory recall response after vaccination. We have obtained FDA-IND approval (BB-19304, Sayour) in GBM with SARS-CoV-2 specific amendment (BB-20871) underway to support first-in-human trials of RNA-NPs targeting both GBM and COVID-19.

A 470-nA Quiescent Current and 92.7%/94.7% Efficiency DCT/PWM Control Buck Converter With Seamless Mode Selection for IoT Application

An ultra-low quiescent current dual-mode buck converter system is designed for IoT application, which includes a double clock time (DCT) and a pulse-width-modulation (PWM) control modes. The proposed DCT mode can reduce the conversion loss over a wide loading range from nA-to-mA and achieve seamless mode transition from DCT to PWM control. Implemented in a $0.18\mu \text{m}$ CMOS, this converter achieves a peak efficiency of 92.7%/94.7% in DCT/PWM and >80% efficiency from $10~\mu $ A to 50 mA (5000x), with a wide input voltage from 2 V to 5 V. A quiescent current of 470 nA including bandgap voltage reference and internal oscillator is achieved. The DCT-to-PWM mode selection mechanism achieves an undershoot of 80 mV at $11~\mu \text{s}$ recovery time when load current jumps from $6.67~\mu \text{A}$ to 50 mA.

Signatures of red-shifted foot points in the quiescent coronal loop system

Abstract. We observed quiescent coronal loops using multi-wavelength observations from the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO) on 13 April 2016. The flows at the foot points of such loop systems are studied using spectral data from the Interface Region Imaging Spectrograph (IRIS). The Doppler velocity distributions at the foot points lying in the moss region show the negligible or small flows at the Ni I, Mg II k3, and C II line corresponding to upper photospheric and chromospheric emissions. Significant red shifts (downflows) ranging from 1 to 7 km s−1 are observed at Si IV (1393.78 Å; log⁡(T/K)=4.8), which is found to be consistent with the existing results regarding dynamical loop systems and moss regions. Such downflows agree well with the impulsive heating mechanism reported earlier.

Morphology Investigation on Cyclopentane Hydrate Formation/Dissociation in a Sub-Millimeter-Sized Capillary

The formation, dissociation, and reformation of cyclopentane (CP) hydrate in a sub-millimeter-sized capillary were conducted in this work, and the morphology of CP hydrate was obtained during above processes, respectively. The influences of the supercooling degree, i.e., the hydrate formation driving force, on CP hydrate crystals’ aspect and growth rate were also investigated. The results demonstrate that CP forms hydrate with the water melting from ice at the interface between the CP and melting water at a temperature slightly above 273.15 K. With the action of hydrate memory effect, the CP hydrate in the capillary starts forming at the CP-water interface or CP–water–capillary three-phase junction and grows around the CP–water interface. The appearance and growth rate of CP hydrate are greatly influenced by the supercooling degree. It indicates that CP hydrate has a high aggregation degree and good regularity at a high supercooling degree (or a low formation temperature). The growth rate of CP hydrate crystals greatly increases with the supercooling degree. Consequently, the temperature has a significant influence on the formation of CP hydrate in the capillary. That means the features of CP hydrate crystals in a quiescent system could be determined and controlled by the temperature setting.

An Improved Orbital Period for GY Cancri Based on Two K2 Campaigns

GY Cnc is a deeply eclipsing cataclysmic variable star with an orbital period of 4.21 hours that has shown several dwarf nova outbursts. The variable was continuously observed by the K2/Kepler satellite with a short cadence in Campaign 5 (C05) for 75 days during 2015. The star was again observed in 2017/2018 for 80 consecutive days during Campaign 16 (C16). 419 well-observed eclipses were measured over C5 and 446 timings were determined in C16. A new ephemeris was calculated combining the K2 data, previously published timings, new light curves from the KELT Follow-Up Network, and additional observations in the AAVSO database. We have refined the orbital period of GY Cnc and improved its ephemeris which had accumulated an error of about 300s over 18 years. A quadratic term was not found to be significant indicating that there is currently no detectable orbital period derivative. We observed a correlation between the quiescent system brightness and the eclipse timing residuals that are as large as +/-15s in the K2 data.

Morphology Study on the Effect of Thermodynamic Inhibitors during Methane Hydrate Formation in the Presence of NaCl

In this study, we investigate the morphology of methane hydrate formation and growth in the presence of well-known thermodynamic inhibitors, monoethylene glycol (MEG) and methanol (MeOH) in a quiescent system. Morphology changes observed during the growth of methane hydrate while employing 5 wt % MEG and MeOH solutions in the presence and absence of NaCl are presented. When 5 wt % of MEG or MeOH was present in an aqueous solution individually, hydrate grew predominantly within the bulk solution featuring a “ridge”-shaped formation above the interface. In the presence of 3.5 wt % NaCl, an enhanced inhibition was observed for methane hydrates formed from 5 wt % MEG solution with limited hydrate growth in the bulk solution and above the gas-liquid interface. In contrast, 5 wt % MeOH solution in the presence of 3.5 wt % NaCl resulted in an increased hydrate growth in bulk (compared to the system without NaCl) and on the reactor wall above the gas–liquid interface, implying a weak promotion rather than the inh...