Pressure Carbon Research Articles

Preparation of starch-derived porous carbon with improved yield by autogenic pressure carbonization and KOH activation for high-performance supercapacitor

Preparation of starch-derived porous carbon with improved yield by autogenic pressure carbonization and KOH activation for high-performance supercapacitor

Polar Acylamide Functionalized Porous Cu-MOFs for Sustainable and Selective Carbon Dioxide Sorption and Separation at Ambient and High Pressure

Metal–organic frameworks with suitable voids and polar functional group are expectant candidates for their excellent carbon dioxide uptake. Herein, two new polar acylamide-functionalized three-dimensional Cu(II)-MOFs have been synthesized, namely, {[Cu2(4-pmi)(glut)2]·(H2O)8}n (1) and {[Cu(4-pmi)(2-ntp)]·(H2O)4}n (2) (4-pmi = pyridine-4-yl-methylene-isonicotinohydrazide, glut = glutarate, and 2-ntp = 2-nitroterephthalate). The dehydrated framework of these two materials demonstrates a moderately high carbon dioxide uptake at ambient pressure (1 bar and 195 K) and high pressure (20 bar and 273 K) for both compounds, 1 and 2. Excitingly, high pressure carbon dioxide sorption of these two compounds, 1 and 2, shows high uptake of 187 and 233 cc/g, respectively. Here, the favorable pore-centric orientation of the acylamide functional group and interaction with the quadruplolar carbon dioxide molecule make such unprecedented results of carbon dioxide sorption. These compounds will be an appropriate commander for their potential application of selective and sustainable carbon dioxide scavenging from industrial flue gas and natural gas.

Modeling study on a two-stage hydrogen purification process of pressure swing adsorption and carbon monoxide selective methanation for proton exchange membrane fuel cells

A two-stage hydrogen purification process based on pressure swing adsorption (PSA) and CO selective methanation (CO-SMET) is proposed to meet the stringent requirements of H2-rich fuel for kW-scale skid-mounted or distributed proton exchange membrane fuel cell systems. The reforming gas is purified using dynamic adsorption model of PSA with activated carbon for initial purification and then kinetic model of CO-SMET with 50 wt% Ni/Al2O3 for CO deep removal. Sensitive analyses of the gas hourly space velocity, adsorption time and adsorption pressure etc. are studied. The results show that excellent H2 purity and CO concentration below 1000 ppm for the initial target using the three-bed and four-bed PSA system at shorter adsorption time and higher pressure, and then CO concentration below 10 ppm with H2 purity over 99.94% on CO-SMET. This work provides a small-scale and hydrogen-saving process for hydrogen purification can be achieved by the two-stage process.

The secondary pore development model of coarse-grained deposition: A case study of the Xiazijie Formation in the Northwestern Margin of the Junggar Basin

The coarse-grained glutenite rock mass of the proximal fan delta is characterized by the blocky texture, mixing of gravels with varied sizes, high mud content, and low porosity and permeability, leading to difficulties in assessment and exploration of oil and gas enrichment regularities of tight glutenite. The Permian Xiazijie Formation in the northwest margin of Junggar Basin has a set of tight glutenite reservoirs, and the reservoir quality is an important controlling factor for oil and gas enrichment. Based on three-dimensional earthquake, casting thin sections, rock physical property, geochemistry, the sedimentary facies division, petrologic features, physical property regularities, pore types and diagenesis of Xiazijie Formation were analyzed. This research develops the pore evolution model of the coarse-grained deposition via the quantitative analysis of porosity evolution. First, during the rapid compaction, intensive mechanical compaction results in reduction of the original porosity from 29.8% to 15.1%. Secondly, the cement formed during the eodiagenesis destructs the reservoir space and leads to an average porosity loss of 6.5%. Third, dissolution effectively improves reservoir quality. It mainly dissolves the zeolite cement, and the porosity grows to 12.1% from 8.6%. The dissolution occurs during the main hydrocarbon expulsion stage of the source rock, which is in favor of hydrocarbon emplacement. Fourth, during the telodiagenesis with the deepening burial and intensifying pressure solution, siliceous and carbonate cement precipitate, the reservoir physical property is degraded again, the porosity loss is about 3.4%. After a series of complex diagenetic processes, the current tight glutenite reservoir comes into being, with the porosity of about 8.7%. The research results provide theoretical reference for coarse-grained glutenite reservoir prediction.

Comparative studies on promotional effect of Pr6O11, Nd2O3 and Sm2O3 on Ni–SiO2 for pressurized carbon dioxide reforming of methane

The 7 wt% rare earth metal oxide promoted Ni–SiO2 catalysts of Ni–7Pr6O11–SiO2, Ni–7Nd2O3–SiO2, and Ni–7Sm2O3–SiO2 were prepared by the complex-decomposition method, and were comparatively evaluated for pressurized carbon dioxide reforming of methane (CRM) under severe conditions of 750 °C, 1.0 MPa, CH4/CO2 = 1, and gas hourly space velocity of 53200 mL/(g·h). The addition of rare earth metal oxide does not affect the Ni dispersion, and all of the catalysts show similarly high Ni dispersion of 16.0% ± 0.2%. As a result, all of the catalysts are highly active for pressurized CRM, the initial CH4 conversions of which approach the thermodynamic equilibrium (47.0% ± 0.2%). In contrast, a clearly favorable effect of the added rare earth metal oxide on the stability of Ni–SiO2 was revealed from the CRM results for a time-on-stream of 50 h, and the highest stability without an observable decrease in the conversions of CH4 and CO2 was obtained over Ni–7Sm2O3–SiO2. Based on the characterization results of thermogravimetric differential scanning calorimetry (TG-DSC) and transmission electron microscopy (TEM), the improved stability of Ni–7Pr6O11–SiO2, Ni–7Nd2O3–SiO2, and Ni–7Sm2O3–SiO2 for pressurized CRM was manifested mainly as the suppressed formation of carbon nanotubes over the catalyst surface, the extent of which is dependent on the specific rare earth metal oxide. Moreover, the consecutive temperature programmed surface reaction of CH4, CO2, and O2 over Ni–7Sm2O3–SiO2 vigorously reveals that the addition of Sm2O3 into Ni–SiO2 inhibits the CH4 decomposition but enhances the oxidization of the carbon species by CO2, leading to the well-balanced rates for forming and removing the coke over Ni–7Sm2O3–SiO2. These findings are not only beneficial to deeply understanding the promotional effect of rare earth metal oxides on Ni-based catalysts for CRM, but also important for extending the application of the less studied rare earth metal oxides as promoters for the metal-supported catalysts.

Ventilatory targets following brain injury.

Recent studies have focused on identifying optimal targets and strategies of mechanical ventilation in patients with acute brain injury (ABI). The present review will summarize these findings and provide practical guidance to titrate ventilatory settings at the bedside, with a focus on managing potential brain-lung conflicts. Physiologic studies have elucidated the impact of low tidal volume ventilation and varying levels of positive end expiratory pressure on intracranial pressure and cerebral perfusion. Epidemiologic studies have reported the association of different thresholds of tidal volume, plateau pressure, driving pressure, mechanical power, and arterial oxygen and carbon dioxide concentrations with mortality and neurologic outcomes in patients with ABI. The data collectively make clear that injurious ventilation in this population is associated with worse outcomes; however, optimal ventilatory targets remain poorly defined. Although direct data to guide mechanical ventilation in brain-injured patients is accumulating, the current evidence base remains limited. Ventilatory considerations in this population should be extrapolated from high-quality evidence in patients without brain injury - keeping in mind relevant effects on intracranial pressure and cerebral perfusion in patients with ABI and individualizing the chosen strategy to manage brain-lung conflicts where necessary.

Statistical Study of the Effectiveness of Surface Application of Graphene Oxide as a Coating for Concrete Protection

Improving the protection of concrete by applying graphene oxide (GO) as a surface treatment has become the objective of the present study. This study focuses on performing a statistical analysis to study different levels of GO application as an exterior coating, thus observing the effectiveness of the coating and the optimization of the treatment material for concrete protection. Four tests were performed to define concrete durability, such as pressurized water penetration, capillary absorption, freeze-thaw resistance and carbonation resistance. The results showed an increase in concrete durability with any level of GO application on the surface, considering that the optimum amount of application for water impermeability and freeze-thaw resistance is 26.2 µg/cm2, since it was possible to reduce pressurized water penetration by 45%, capillary water absorption by 57% and freeze-thaw detachment by 25%. However, the optimum application rate for carbonation resistance is 52.4 µg/cm2, reducing carbonation by almost 60%. In conclusion, if the concrete is going to be exposed to less aggressive environments, the application of a mild surface coating of GO is sufficient for its protection, and if the concrete is going to be exposed to more aggressive environments, it is necessary to increase the amount of GO. The performance of GO as a coating significantly increased the degree of protection of the concrete, increasing its service life and proving to be a promising treatment for concrete surface protection.

Noninvasive carbon dioxide monitoring in pediatric patients undergoing laparoscopic surgery: transcutaneous vs. end-tidal techniques

PurposeThe present study aimed to investigate the correlation between transcutaneous carbon dioxide partial pressure (PtcCO2) and arterial carbon dioxide pressure (PaCO2) and the accuracy of PtcCO2 in predicting PaCO2 during laparoscopic surgery in pediatric patients.MethodsChildren aged 2–8 years with American Society of Anesthesiologists (ASA) class I or II who underwent laparoscopic surgery under general anesthesia were selected. After anesthesia induction and tracheal intubation, PtcCO2 was monitored, and radial arterial catheterization was performed for continuous pressure measurement. PaCO2, PtcCO2, and end-tidal carbon dioxide partial pressure (PetCO2) were measured before pneumoperitoneum, and 30, 60, and 90 min after pneumoperitoneum, respectively. The correlation and agreement between PtcCO2 and PaCO2, PetCO2, and PaCO2 were evaluated.ResultsA total of 32 patients were eventually enrolled in this study, resulting in 128 datasets. The linear regression equations were: PtcCO2 = 7.89 + 0.82 × PaCO2 (r2 = 0.70, P < 0.01); PetCO2 = 9.87 + 0.64 × PaCO2 (r2 = 0.69, P < 0.01). The 95% limits of agreement (LOA) of PtcCO2 – PaCO2 average was 0.66 ± 4.92 mmHg, and the 95% LOA of PetCO2 – PaCO2 average was –4.4 ± 4.86 mmHg. A difference of ≤ 5 mmHg was noted between PtcCO2 and PaCO2 in 122/128 samples and between PetCO2 and PaCO2 in 81/128 samples (P < 0.01).ConclusionIn pediatric laparoscopic surgery, a close correlation was established between PtcCO2 and PaCO2. Compared to PetCO2, PtcCO2 can estimate PaCO2 accurately and could be used as an auxiliary monitoring indicator to optimize anesthesia management for laparoscopic surgery in children; however, it is not a substitute for PetCO2.Registration number of Chinese Clinical Trial RegistryChiCTR2100043636.

Clinical Performance of I-gel versus Ambu AuraGain in Paediatric Patients undergoing General Anaesthesia: A Randomised Clinical Study

Introduction: Newer second-generation Supraglottic Airway Devices (SADs) are easy to insert and provide a smooth induction of anaesthesia with minimal haemodynamic pressor response. The paediatric I-gel and Ambu AuraGain are newer SADs that are increasingly being used as alternatives to endotracheal intubation in the paediatric population. Aim: To compare the clinical performance of I-gel and Ambu AuraGain in children undergoing general anaesthesia with respect to ease of insertion, haemodynamic changes, and the frequency and severity of postoperative sore throat. Materials and Methods: This randomised clinical study included 100 children aged 2 to 10 years, belonging to American Society of Anaesthesiologists (ASA) Grade I and II, scheduled for elective surgery under general anaesthesia. They were randomly allocated to Group I (I-gel) and Group A (Ambu AuraGain), comprising 50 patients each. The time taken for SAD placement, the number of attempts, ease of insertion, and the requirement of additional airway manipulations during insertion were observed. Haemodynamic Parameters Heart Rate (HR), Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), Mean Arterial Pressure (MAP), SpO2 , and End-tidal Carbon Dioxide [ (EtCO2 ) ]) during the procedure were observed. The frequency and severity of postoperative sore throat were assessed between both groups. Descriptive statistics were applied to all data and reported in terms of mean, Standard Deviation (SD), and percentages, and appropriate statistical tests of comparison were applied. Results: In this study, the demographic data of patients, such as age, weight, gender, and ASA status, were comparable in both groups. There was no statistically significant difference in the time taken for successful SAD placement and the number of attempts required to do the same. Ambu AuraGain was easier to insert than I-gel (p-value&lt;0.05). I-gel required a significantly higher number of additional airway manipulations during insertion compared to Ambu AuraGain (20% in Group I versus 4% in Group A). Haemodynamic parameters were comparable between both groups at all time intervals. The frequency and severity of postoperative sore throat were statistically non significant between I-gel and Ambu AuraGain. Conclusion: Both the I-gel and Ambu AuraGain are reliable and safe devices for maintaining an adequate airway in paediatric patients. However, Ambu AuraGain was easier to insert and required fewer airway manipulations than I-gel during insertion, making it a favourable choice.

Evaluation of failure fraction for high burnup High Temperature Gas-cooled Reactor fuel

In high temperature gas-cooled reactors (HTGRs), Tri-isotropic (TRISO)-coated fuel particles are employed as fuel. In the high burnup coated fuel particle, stress due to fission gas pressure and irradiation-induced pyrolytic carbon (PyC) shrinkage is introduced into the coating layers and consequently the stress could cause failure of coating layers under high burnup irradiation condition. A failure model has developed to predict failure fraction of TRISO-coated particle under high burnup irradiation. In the model, failure probability is strongly dependent on the irradiation characteristics of PyC. This paper describes the outline of the failure model and evaluation result of high burnup fuel irradiation experiment by the model.

Numerical Investigation of Jet Impingement Cooling with Supercritical Pressure Carbon Dioxide in a Multi-Layer Cold Plate during High Heat Flux

Numerical Investigation of Jet Impingement Cooling with Supercritical Pressure Carbon Dioxide in a Multi-Layer Cold Plate during High Heat Flux

Consequences of Different Pressures and Electrolytes on the Irreversible Expansion of Lithium Metal Half Cells

AbstractLithium metal is considered as the ‘holy‐grail’ among anode materials for lithium‐ion batteries, but it also has some serious drawbacks such as the formation of dendritic and dead lithium. In this study, the interplay of external pressure and different carbonate‐ and ether‐based electrolytes on the (ir)reversible expansion of lithium metal during cycling against lithium titanate and lithium iron phosphate is studied. In carbonate‐based electrolytes without any additives, lithium metal shows tremendous irreversible expansion and significant capacity reduction at elevated current densities due to the formation of mossy and dead lithium. The addition of fluoroethylene carbonate can reduce irreversible expansion and capacity reduction, especially when a high external pressure is applied. When an ether‐based electrolyte is used, the irreversible dilation of the lithium metal is suppressed when applying increased external pressures. Overall, increased external pressure appears to reduce the formation of mossy and dead lithium and improve the performance.

Inactivation of Saccharomyces cerevisiae by combined high pressure carbon dioxide and high pressure homogenization

A combined treatment of high pressure carbon dioxide (HPCD) and high pressure homogenization (HPH) was investigated to inactivate Saccharomyces cerevisiae in a phosphate buffered solution. The inactivation kinetics, protein leakage, particle size distribution, SEM images, and TEM images of Saccharomyces cerevisiae exposed to HPH alone, HPCD alone, and the combined treatment of HPCD and HPH (HPCD+HPH) were studied. Results showed that HPCD+HPH was superior to HPH alone and HPCD alone in the inactivation of Saccharomyces cerevisiae. The inactivation kinetics of the combined treatment exhibited a fast-slow biphasic curve. The synergic bactericidal ability of HPCD+HPH could be attributed to the enhancing effect of HPH on CO2 germicidal capability. The possibility of the combination of HPH and HPCD for microbial inactivation of Saccharomyces cerevisiae was validated, and the combined treatment has the potential to be a viable approach for microbial inactivation.

Production of concrete pipes by carbonation curing in an inflatable enclosure

Production of concrete pipes using ambient pressure (AP) carbonation curing in an inflatable enclosure was studied. The process was developed to replace traditional steam curing in order to reduce energy consumption, improve concrete performance and sequester carbon dioxide in pipes. The ambient pressure carbonation was compared with high pressure (HP) carbonation at 5 bar and normal hydration references. A composite structure of calcium carbonate with CSH was found in concrete after AP carbonation. Multiple techniques including quantitative X-ray diffraction analysis (QXRD), thermogravimetry analysis (TGA), Raman spectroscopic analysis, and scanning electron microscopy (SEM) were applied to characterize the strength development and microstructural enhancement of such cementitious matrix. The results demonstrated that AP carbonated pipes had comparable CO2 uptake, three-edge-bearing test (TEBT) strength, absorption, and resistance to internal-hydraulic pressure with HP carbonated ones. In addition, AP carbonation provided nucleating sites for CSH gel growth, thus contributing to the improved performance of concrete pipes while sequestrating CO2 and reducing the overall carbon footprint. Lastly, the carbon sequestration cost is lower in AP than in HP carbonation, which confirms the economic benefits of using AP in early-age carbonation curing of cement-based products.

Operating Range, Performance and Emissions of an HCCI Engine Fueled with Fusel Oil/Diethyl Ether: An Experimental Study

The main disadvantages of HCCI engines are the knocking tendency at high engine loads, the challenge of the start of the combustion, control of the combustion phase, and the narrow operating range. In this study, we aimed to control the combustion processes in HCCI engines and to expand their working range by improving the fuel properties of fusel oil by the addition of diethyl ether. Thus, the variations in the in-cylinder pressure, rate of heat release, indicated mean effective pressure, start of combustion, combustion duration, CA50, indicated thermal efficiency, mean pressure rise rate, hydrocarbon and carbon monoxide emissions were investigated. It was observed that the in-cylinder pressure and rate of heat release were taken into advance and the test engine could be operated for a wider range by increasing the diethyl ether ratio in the blend. The indicated mean effective pressure increased by 67.5% with DEE40 fuel compared to the DEE80. Under the same operating conditions, HC and CO emissions decreased by 41.6% and 56.2%, in use of DEE40. Furthermore, the highest indicated thermal efficiency was obtained as 42.5% with DEE60 fuel. Maximum hydrocarbon and carbon monoxide emissions were observed with DEE80 fuel as 0.532% and 549 ppm, respectively.

Multiobjective design optimization of parabolic trough collectors

Despite the large amount of research conducted on PTC performance analysis, few and rare numbers of research have considered the design optimization of PTCs. In the present work, a novel multiobjective-optimization model is developed for design optimization of PTCs. The objective functions are the thermal and exergetic efficiencies because they are the most important performance indicators (PIs) of PTCs. The design variables are the inlet temperature, and the outlet and inlet diameters of the PTC receiver tube. The PTC material volume (refers to the volume of the PTC receiver and collector) is kept constant throughout the optimization process to enhance the PTC performance without incurring additional cost (material). A parametric analysis is conducted before the optimization. The inlet-mass flow-rate effect is found to be negligible in contrast to the inlet temperature. Therefore, the latter is considered as a design parameter in the optimization process. Nine thermal fluids are used in the present optimization, which include pressurized water, Therminol, molten salt, liquid sodium, Syltherm, air, carbon dioxide, helium and hydrogen. The present optimization model is found to be efficient in maximizing both the thermal and exergetic efficiencies. Water achieves maximum optimal thermal efficiency, whereas helium achieves maximum optimal exergetic efficiency. Liquid sodium exhibits the best PI (60.725).

Clinical study of multifunctional laryngeal mask in airway interventional therapy.

This study is conducted to evaluate the efficacy and safety of using multifunctional intubation laryngeal masks with normal frequency jet ventilation in airway interventional therapy. A total of 200 patients receiving airway interventional therapy were enrolled in this retrospective study and were divided into 2 groups (group M and group P) by doctors in our hospital to compare the effect of different laryngeal masks. Group M used common laryngeal masks and an anesthesia machine for positive pressure ventilation while group P took multifunctional intubation laryngeal masks and used a jet ventilator for normal frequency jet ventilation. The patients' mean arterial pressure, heart rate, arterial oxygen partial pressure (PaO2) and arterial carbon dioxide partial pressure (PaCO2), and the operation time, recovery score and the patients' and doctors' satisfaction levels were compared between the 2 groups. Both groups were hemodynamically stable, and their PaO2 levels were significantly higher before the operation than that during and after the operation (P < .05). Compared with group M, the PaCO2 level of group P was more stable both during and after the operation, and this difference was statistically significant (P < .05). There was no statistically significant difference in terms of the 2 group's operating time, recovery score, and patients' satisfaction levels (P > .05). However, the satisfaction levels of doctors in group P were higher than that in group M, and this difference was statistically significant (P < .05). As statistics show, the intraoperative hemodynamics and PaO2 and PaCO2 levels were stable, and patients, surgeons and anesthesia operators were satisfied. Therefore, it is feasible to apply multifunctional intubation laryngeal masks with normal frequency jet ventilation in airway interventional therapy and it is a safe and ideal way to ensure ventilation.

Detection of increased intracranial pressure in trans-oral robotic thyroidectomy using optic nerve sheath diameter measurement.

During transoral robot-assisted thyroidectomy, there is a risk of increasing intracranial pressure because the site of CO2 insufflation is narrow and close to the brain. We analyzed the pre- to post-CO2 neck insufflation change in the optic nerve sheath diameter during transoral robot-assisted thyroidectomy. Changes in vital-signs, airway pressure, and arterial carbon dioxide pressure were analyzed along with postoperative complications. Among the 30 participants, the post-CO2 inflation mean optic nerve sheath diameter (5.64 ± 0.54 mm) was higher than the pre-induction diameter (4.81 ± 0.37 mm) with a mean difference of 0.83 (95% CI, 0.69-0.97; p < 0.001), but returned to baseline after CO2 deflation in most cases. One participant had sustained increased optic nerve sheath diameter (6.35 mm) associated with severe new-onset postoperative headache. Transient elevation in the intracranial pressure during low-pressure CO2 neck insufflation in the transoral robot-assisted thyroidectomy did not appear to adversely affect patients.

High performance carbon nanotubes thin film transistors by selective ferric chloride doping

Single wall carbon nanotubes (SWNT) have been a significant research topic as active layers for thin film transistors (TFTs) due to their high charge carrier mobility beyond that of crystalline silicon. In this study, we report an effective approach to achieve a very high field-effect mobility and on/off ratio for solution processed semiconducting SWNT TFTs, by selective doping through contact with a thin ferric chloride (FeCl3) dopant layer. The semiconducting layer is formed by a double spin coating of the highly purified (>99%) high pressure carbon mono oxide (HiPCO) SWNT sorted by wrapping of poly (3-dodecylthiophene-2,5-diyl) (P3DDT). In order to achieve effective hole injection from the top Au source electrode without increasing the off-state drain current, less purified (98-99%) SWNTs produced by the plasma discharge process sorted by wrapping of poly (9,9-di-n-dodecylfluorene) (PFDD) are formed on the top of HiPCO film. Significantly improved TFT performance is achieved by the insertion of a few nanometers of a FeCl3 dopant layer at the semiconductor-contact interface. A significant high hole field-effect of 48.35 ± 3.11 cm2V−1s−1 (bare: 6.18 ± 0.87 cm2V−1s−1) with a reasonable on/off current ratio of 105, and low off current of ∼80 pA, are obtained by controlling the concentration of FeCl3 dopant (thickness = 1.5 nm) at the contact. Mobility is improved further at 2.5 nm thickness of the FeCl3 dopant layer resulting in a hole mobility of 177 ± 13.2 cm2 V−1s−1, an on/off ratio of 7.4 × 103, and off state current of 1.2 × 10−9 A.

Effect of dilution solvent and injection volume on the analysis of basic hydrophilic therapeutic polypeptide salts with pressurized carbon dioxide mobile phases

The chromatographic analysis of long-chain hydrophilic therapeutic peptides, with molecular weight mostly in the 3500–4500 Da range (31–34 amino acids), is explored with pressurized CO2 in the mobile phase. The optimal method was obtained on a Torus 2-PIC column, with a gradient elution of 50–90% co-solvent in CO2, which is relevant of enhanced-fluidity liquid chromatography (EFLC). Both UV (210 nm) and mass spectrometric detection modes were employed to assess the purity of the major peak and its resolution from impurities. Ten out of the eleven peptides in this set were basic, thus they were analyzed as acetate or trifluoroacetate salts. As significant peak distortion was observed in some cases, thorough examination of dilution solvent and injection volume was conducted to improve peak shape and resolution from impurities. Finally, the best injection volume was 1 µL, as any other volume (smaller or larger) yielded distorted peaks, and the best dilution solvent composition was the same as the mobile phase co-solvent (methanol comprising 5% water and 0.1 % methanesulfonic acid). However, not all peptide salts were fully soluble in this solvent so other alternatives (including more water in the dilution solvent), offering adequate dissolution but slightly inferior chromatographic performance should be chosen in such cases.