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1.
J Community Health ; 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38668811

ABSTRACT

Nearly 60% of people with HIV in New York State are over 50 years of age. After town halls and a statewide survey of long-term survivors, older people living with HIV, and their providers, the Quality of Care Program of the AIDS Institute in the New York State Department of Health developed a statewide quality improvement project that aimed to improve screening for functional impairments among people aging with HIV. Thirteen sites reported outcomes of a pilot project using a modification of the World Health Organization's Integrated Care of Older People (ICOPE) intrinsic capacity screen in small scale, short cycle tests of change. A total of 1,629 people were found to be eligible for screening, and of these, 638 people were screened. Both clinical and non-clinical sites were able to identify significant areas of need. Positive screens ranged from a low of 17% for the identification of hearing issues to 49% for vision concerns. Only 11% of people with memory or nutritional concerns were referred for services; hearing loss was the domain with the largest number of referrals, at 27%. Although in many cases, when referrals were not made, patients/clients were already under care for the identified functional deficit, in other cases no services were available for referral or patients/clients declined to use the offered service. Sites also responded to the findings of the screen by initiating process changes, and many reported continuing to screen for functional impairments after the close of the pilot. The modified ICOPE screen is still in use in sites throughout the state. This pilot demonstrated that a collaboration between people with lived HIV experience, the New York State Department of Health, clinicians, and service providers could result in improved quality of care for people aging with HIV.

2.
J Emerg Nurs ; 50(3): 342-353, 2024 May.
Article in English | MEDLINE | ID: mdl-38597852

ABSTRACT

INTRODUCTION: The national pediatric mental and behavioral health crisis dramatically increased emergency department mental and behavioral health visits and changed emergency nursing practice. Acuity assessment determines patient severity level and supports appropriate resources and interventions. There are no established nursing tools that assess pediatric mental or behavioral health acuity in the emergency department setting. Our goal was to develop and implement the novel pediatric emergency nurse Emergency Behavioral Health Acuity Assessment Tool. METHODS: This quality-improvement project used the plan, do, study, act model to design/refine the Emergency Behavioral Health Acuity Assessment Tool and a non-experimental descriptive design to assess outcomes. The setting was a 47-bed urban level 1 pediatric trauma center with more than 60,000 annual visits. The team designed the tool using published evidence, emergency nurse feedback, and expert opinion. The tool objectively captured patient acuity and suggested acuity-specific nursing interventions. Project outcomes included acuity, length-of-stay, restraint use, and patient/staff injuries. Analyses included descriptive statistics and correlations. RESULTS: With over 3000 annual mental/behavioral-related visits, the emergency department had an average daily census of 23 mental and behavioral health patients. Implementation occurred in August 2021. The Emergency Behavioral Health Acuity Assessment Tool dashboard provided the number of patients, patient location, and acuity. Length-of-stay did not change; however, patient restraint use and patient/staff injuries declined. Number of restraints positively correlated with moderate acuity levels (r = 0.472, P = 0.036). DISCUSSION: For emergency nurses, the Emergency Behavioral Health Acuity Assessment Tool provided an objective measure of patient acuity. Targeted interventions can improve the care of this population.


Subject(s)
Emergency Nursing , Emergency Service, Hospital , Pediatric Nursing , Quality Improvement , Humans , Emergency Nursing/methods , Child , Pediatric Nursing/methods , Mental Disorders/nursing , Mental Disorders/diagnosis , Nursing Assessment/methods , Patient Acuity , Female , Male
3.
J Chem Phys ; 159(10)2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37702360

ABSTRACT

Superconcentrated aqueous electrolytes have recently emerged as a new class of electrolytes, called water-in-salt electrolytes. They are distinguished, in both weight and volume, by a quantity of salt greater than water. Currently, these electrolytes are attracting major interest, particularly for application in aqueous rechargeable batteries. These electrolytes have only a small amount of free water due to an ultrahigh salt concentration. Consequently, the electrochemical stability window of water is wider than the predicted thermodynamic value of 1.23 V. Hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) have been shown to be shifted to more negative and positive potentials, respectively. The decrease in free water population is recognized as being involved in the increase in the electrochemical stability window of water. Here, we study the quantitative contribution of the decrease in the free water molecule concentration to the permittivity of the solution and of the activity of water to the OER and HER overpotentials when the salt concentration increases. We compare our model with that of Kornyshev and get three types of electrolyte structures: diluted, gradient of water contents, and aggregation. The theoretical calculation of the redox potentials of the OER and HER is compared with the experimentally determined electrochemical properties of aqueous LiTFSI electrolytes.

4.
Soft Matter ; 13(37): 6639-6646, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28926070

ABSTRACT

Diazonium chemistry concomitant with in situ electrochemical reduction was used to graft an aryl aldehyde to indium-tin oxide (ITO) coated glass substrates. This served as an anchor for preparing electroactive azomethines that were covalently bonded to the transparent electrode. The immobilized azomethines could undergo multiple step-wise component exchanges with different arylamines. The write-erase-write sequences were electrochemically confirmed. The azomethines could also be reversibly hydrolyzed. This was exploited for multiple azomethine-hydrolysis cycles resulting in discrete electroactive immobilized azomethines. The erase-rewrite sequences were also electrochemically confirmed.

5.
Phys Chem Chem Phys ; 18(28): 19137-45, 2016 Jul 28.
Article in English | MEDLINE | ID: mdl-27356866

ABSTRACT

The self-discharge of hybrid electrochemical capacitors based on the redox activity of electrolyte additives or grafted species to the electrode material is investigated simultaneously for the cell and each individual electrode. Electrochemical capacitors using a redox-active electrolyte consisting in hydroquinone added to the electrolyte solution and a redox-active electrode based on anthraquinone-grafted carbon as a negative electrode are investigated. The results are analyzed by using Conway kinetic models and compared to those of a common electrochemical double layer capacitor. The self-discharge investigation is complemented by charge/discharge cycling and it is shown that processes affecting galvanostatic charge/discharge cycling and the self-discharge rate occurring at each electrode of an electrochemical capacitor are different but related to each other. The electrochemical capacitor containing hydroquinone in the electrolyte exhibits a much quicker self-discharge rate than that using a negative electrode based on grafted anthraquinone with a 50% decay of the cell voltage of the fully charged device in 0.6 and 6 h, respectively. The fast self-discharge of the former is due to the diffusion of benzoquinone molecules (formed at the positive electrode during charging) to the negative electrode, where they are reduced, causing a quick depolarization. The grafting of anthraquinone molecules on the carbon material of the negative electrode led to a much slower self-discharge, which nonetheless occurred, by the reaction of the reduced form of the grafted species with electrolyte species.

6.
Angew Chem Int Ed Engl ; 55(17): 5318-21, 2016 Apr 18.
Article in English | MEDLINE | ID: mdl-26997572

ABSTRACT

A promising strategy for increasing the performance of supercapacitors is proposed. Until now, a popular strategy for increasing the specific capacity of the electrode consists of grafting redox molecules onto a high surface area carbon structure to add a faradaic contribution to the charge storage. Unfortunately, the grafting of molecules to the carbon surface leads to a dramatic decrease of the electrochemical performances of the composite material. Herein, we used the organic binder as an active material in the charge/discharge process. Redox molecules were attached onto its polymeric skeleton to obtain a redox binder with the dual functionalities of both the binder and the active material. In this way, the electrochemical performance was improved without detrimentally affecting the properties of the porous carbon. Results showed that the use of a redox binder is promising for enhancing both energy and power densities.

7.
Langmuir ; 30(22): 6612-21, 2014 Jun 10.
Article in English | MEDLINE | ID: mdl-24811121

ABSTRACT

The electrochemical reduction of 1,10-phenanthroline in aqueous acidic electrolyte at a glassy carbon electrode led to the covalent modification of the electrode. Thereafter, the deposited film can be switched to an electroactive form by electrochemical oxidation. An electroactive film can be also generated by alternate reductive and oxidative voltammetric cycling in a 1,10-phenanthroline/aqueous sulfuric acid solution. First, the electrochemical procedure for the formation of a film is presented. Second, the morphology and chemical structure of 1,10-phenanthroline coatings were investigated by atomic force microscopy, time-of-flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy, and electrochemical techniques. The ultrathin (<15 nm) electrodeposited films consist of oligomeric species. The coatings deposited in alternate and/or continuous reductive and oxidative steps contain oxygen atoms incorporated into the oligomer backbone. The preliminary results point out the formation of a dione derivative that is responsible for the electroactivity of the grafted layer.


Subject(s)
Carbon/chemistry , Electrochemistry/methods , Electrodes , Phenanthrolines/chemistry , Microscopy, Atomic Force , Photoelectron Spectroscopy
8.
J Phys Chem B ; 127(13): 2979-2990, 2023 Apr 06.
Article in English | MEDLINE | ID: mdl-36952601

ABSTRACT

Water-in-salt electrolytes constitute a new class of materials that have distinct properties relative to lower-concentration solutions. A recent approach to further increase the salt concentration and decrease the water content includes the addition of an ionic liquid to a highly concentrated aqueous solution. However, the physicochemical and electrochemical properties of aqueous lithium acetate-1-ethyl-3-methylimidazolium acetate solutions as well as the molecular interactions between electrolyte species have not been characterized. Here, we investigate these properties by evaluation of the ionic conductivity, viscosity, and thermal properties as well as the electrochemical behavior of various electrodes in these electrolytes. The intermolecular interactions are probed by nuclear magnetic resonance and infrared spectroscopies. We find that the addition of the ionic liquid increases the solubility limit of lithium acetate and that with an increase in both acetate salt and ionic liquid concentration in the electrolyte and decrease in water concentration, a strong acetate-water network is formed. The electrochemical stability window increases upon addition of the ionic liquid and reaches a value larger than 5 V for a set of negative Al and positive Ti electrodes in the highest acetate salt/ionic liquid concentration. Preliminary electrochemical charge storage performance measurements of a symmetric device based on two porous carbon electrodes cycled at a current density of 25 mA g-1 delivered a specific capacitance of 20 F g-1 with a Coulombic efficiency higher than 99% using a 1.8 V voltage window.

9.
ChemSusChem ; 16(17): e202300399, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37171048

ABSTRACT

Nowadays, solid electrolytes are considered the main alternative to conventional liquid electrolytes in lithium batteries. The fabrication of these materials is however limited by the strict synthesis conditions, requiring high temperatures which can negatively impact the final performances. Here, it is shown that a modification of garnet-based Li7 La3 Zr2 O12 (LLZO) and the incorporation of tellurium can accelerate the synthesis process by lowering the formation temperature of cubic LLZO at temperatures below 700 °C. Optimized synthesis at 750 °C showed a decrease in particle size and cell parameter for samples with higher amounts of Te and the evaluation of electrochemical performances reported for LLZO Te0.25 a value of ionic conductivity of 5,15×10-5  S cm-1 after hot-pressing at 700 °C, two orders of magnitude higher than commercial Al-LLZO undergoing the same working conditions, and the highest value at this densification temperature. Partial segregation of Te-rich phases occurs for high-temperature densification. Our study shows the advantages of Te insertion on the sintering process of LLZO garnet and demonstrates the achievement of highly conductive LLZO with a low-temperature treatment.

10.
Langmuir ; 28(10): 4889-95, 2012 Mar 13.
Article in English | MEDLINE | ID: mdl-22324405

ABSTRACT

The in situ generation of 3-diazonium cations from 3-aminopyridine and their subsequent stability under experimental conditions used for electrografting of pyridine groups were investigated by spectroscopy and electrochemistry. UV spectroscopy revealed the rapid kinetics for the reaction of 3-aminopyridine with sodium nitrite in HCl to form the 3-diazopyridinium cation with a second-order rate constant of 550 ± 20 L mol(-1) s(-1) at 22 °C. UV spectroscopy showed that the 3-diazopyridinium ion was relatively unstable and its transformation into 3-hydroxypyridine was proven by (1)H NMR. Its hydrolytic decomposition was investigated by NMR and followed first-order kinetics with a rate constant of (53 ± 5) × 10(-3) s(-1) at 22 °C. These results enable us to establish the appropriate conditions for the electrografting of pyridine from the corresponding diazonium cations generated in situ. The electrochemical modification of glassy carbon electrodes with pyridine was characterized by cyclic voltammetry and the resulting grafted layer by electrochemical impedance spectroscopy in the presence of Fe(CN)(6)(3-/4-) as redox probes. The effect of diazotization time before electrochemical reduction on the blocking effect of the grafted layer was investigated and showed that an increase of the diazotization time led to less efficient grafting. The presence of immobilized pyridine on the electrode surface was demonstrated by X-ray photoelectron spectroscopy measurements, and a surface coverage of 8.8 × 10(-10) mol cm(-2) was estimated for the grafted pyridine groups. The significance of these results for researchers using the in situ generation approach for electrochemical and chemical grafting is discussed.

11.
Chem Soc Rev ; 40(7): 3995-4048, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21503288

ABSTRACT

Electrografting refers to the electrochemical reaction that permits organic layers to be attached to solid conducting substrates. This definition can be extended to reactions involving an electron transfer between the substrate to be modified and the reagent, but also to examples where a reducing or oxidizing reagent is added to produce the reactive species. These methods are interesting as they provide a real bond between the surface and the organic layer. Electrografting applies to a variety of substrates including carbon, metals and their oxides, but also dielectrics such as polymers. Since the 1980s several methods have been developed, either by reduction or oxidation, and some of them have reached an industrial stage. This critical review describes the methods that are used for electrografting, their mechanism, the formation and growth of the layers as well as their applications (742 references).

13.
ChemSusChem ; 14(12): 2487-2500, 2021 Jun 21.
Article in English | MEDLINE | ID: mdl-33973406

ABSTRACT

Aqueous electrolytes are attractive for applications in electrochemical technologies due to features like being eco-friendly, cost effective, and non-flammable. Very recently, superconcentrated aqueous electrolytes, such as so-called water-in-salt, water-in-bisalt, and hydrate melt, have received a significant attention for electrochemical energy storage due to enhanced stability and much wider electrochemical stability window. This Review focuses on the physicochemical properties of the highly concentrated electrolytes that are derived from several analysis techniques and simulation. A summary of most common features such as ions-water interactions, structure of species present in the electrolyte, conductivity, and viscosity of the electrolytes found in the literature are presented as well. In addition, this Review explains how these characteristics affect the electrochemical behavior of the electrolyte such as double layer structure and electrode/electrolyte interface leading to enhanced electrochemical stability of aqueous electrolytes.

14.
Langmuir ; 26(8): 5991-7, 2010 Apr 20.
Article in English | MEDLINE | ID: mdl-20235524

ABSTRACT

A multistep procedure to prepare heterogeneous structured surfaces with contrasted chemical functionalities at the nanometer scale is presented. Aryldiazonium cations are used for the nanopatterning of electrodes to create hybrid surfaces. The nanopatterning procedure involves the auto-organization of a polystyrene (PS) beads layer at gold or glassy carbon electrode surfaces. The deposited beads layer permits masking of a fraction of the surface from a first aryldiazonium electrografting process. By subsequent removal of the PS beads, the ungrafted surface areas become available for either another aryl diazonium electrografting or a metal electrodeposition, leading to hybrid nanostructured surfaces.

15.
Materials (Basel) ; 13(4)2020 Feb 20.
Article in English | MEDLINE | ID: mdl-32093225

ABSTRACT

In this study, a carbon-coated LiFePO4 (LFP/C) powder was chemically grafted with trifluoromethylphenyl groups in order to increase its hydrophobicity and to protect it from moisture. The modification was carried out by the spontaneous reduction of in situ generated 4-trifluoromethylphenyl ions produced by the diazotization of 4-trifluoromethylaniline. X-ray photoelectron spectroscopy was used to analyze the surface organic species of the modified powder. The hydrophobic properties of the modified powder were investigated by carrying out its water contact angle measurements. The presence of the trifluoromethylphenyl groups on the carbon-coated LiFePO4 powder increased its stability in deionized water and reduced its iron dissolution in the electrolyte used for assembling the battery. The thermogravimetric and inductively coupled plasma atomic emission spectroscopy analyses revealed that 0.2-0.3 wt.% Li was deinserted during grafting and that the loading of the grafted molecules varied from 0.5 to 0.8 wt.% depending on the reaction conditions. Interestingly, the electrochemical performance of the modified LFP/C was not adversely affected by the presence of the trifluoromethylphenyl groups on the carbon surface. The chemical relithiation of the grafted samples was carried out using LiI as the reducing agent and the lithium source in order to obtain fully lithiated grafted powders.

16.
Angew Chem Int Ed Engl ; 48(22): 4006-8, 2009.
Article in English | MEDLINE | ID: mdl-19396848

ABSTRACT

Give me a tip: In situ production of diazonium salts from nitro compounds allows the use of diazonium chemistry for microelectrochemical patterning of surfaces by scanning electrochemical microscopy. The nitro precursor is reduced at the tip to the amine, which is diazotized in the interelectrode space as it diffuses (see picture). The tip acts as a source of diazonium salts, allowing sample derivatization just beneath the tip.

17.
Chemphyschem ; 9(8): 1164-70, 2008 Jun 02.
Article in English | MEDLINE | ID: mdl-18418823

ABSTRACT

Two-component substituted aryl groups are simultaneously grafted onto the surface of a glassy carbon electrode by electrochemical reduction of a binary mixture of two aryl diazonium salts in acetonitrile. The electrochemical deposition is achieved potentiostatically and two different mixtures with four different ratios of diazonium salts are used. The binary mixtures comprise: 1) 4-nitrophenyl diazonium and 4-bromophenyl diazonium cations and 2) 4-bromophenyl diazonium and N,N-diethylaniline diazonium cations. The chemical composition of the two component films is determined by cyclic voltammetry in an electrolyte inert for electroactive groups such as nitrophenyl and bromophenyl. X-ray photoelectron spectroscopy is also used to evaluate the surface concentration of each grafted substituted phenyl group. The surface concentration of the substituted phenyl group for which the corresponding diazonium cation is the most easily reduced is higher than its concentration in the mixture of the deposition solution. The usefulness of binary films is also discussed.

18.
ChemSusChem ; 11(1): 219-228, 2018 01 10.
Article in English | MEDLINE | ID: mdl-29024548

ABSTRACT

The electrochemical reduction of aqueous pyridinium and N-methyl pyridinium ions is investigated in the absence and presence of CO2 and electrolysis reaction products on glassy carbon, Au, and Pt electrodes are studied. Unlike pyridinium, N-methyl pyridinium is not electroactive at the Pt electrode. The electrochemical reduction of the two pyridine derivatives was found to be irreversible on glassy carbon. These results confirmed the essential role of the N-H bond of the pyridinium cation. In contrast, the electrochemical response of N-methyl pyridinium ion at the glassy carbon electrode suggests that a specific interaction occurs between the glassy carbon surface and the aromatic ring of the pyridinium derivative. For all electrodes, an enhancement of current was observed in the presence of CO2 . However, NMR spectroscopy of the solutions following electrolysis showed no formation of methanol or other possible byproducts of the reduction of CO2 in the presence of either pyridinium derivative ion.


Subject(s)
Carbon Dioxide/chemistry , Electrochemical Techniques/methods , Electrolytes/chemistry , Pyridinium Compounds/chemistry , Water/chemistry , Cations , Electrodes , Oxidation-Reduction , Photoelectron Spectroscopy , Proton Magnetic Resonance Spectroscopy
19.
Open Forum Infect Dis ; 5(10): ofy254, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30386808

ABSTRACT

BACKGROUND: The HIV treatment cascade is a tool for characterizing population-level gaps in HIV care, yet most adaptations of the cascade rely on surveillance data that are ill-suited to drive quality improvement (QI) activities at the facility level. We describe the adaptation of the cascade in health care organizations and report its use by HIV medical providers in New York State (NYS). METHODS: As part of data submissions to the NYS Department of Health, sites that provide HIV medical care in NYS developed cascades using facility-generated data. Required elements included data addressing identification of people living with HIV (PLWH) receiving any service at the facility, linkage to HIV medical care, prescription of antiretroviral therapy (ART), and viral suppression (VS). Sites also submitted a methodology report summarizing how cascade data were collected and an improvement plan identifying care gaps. RESULTS: Two hundred twenty-two sites submitted cascades documenting the quality of care delivered to HIV patients presenting for HIV- or non-HIV-related services during 2016. Of 101 341 PLWH presenting for any medical care, 75 106 were reported as active in HIV programs, whereas 21 509 had no known care status. Sites reported mean ART prescription and VS rates of 94% and 80%, respectively, and 60 distinct QI interventions. CONCLUSIONS: Submission of facility-level cascades provides data on care utilization among PLWH that cannot be assessed through traditional HIV surveillance efforts. Moreover, the facility-level cascade represents an effective tool for identifying care gaps, focusing data-driven improvement efforts, and engaging frontline health care providers to achieve epidemic control.

20.
ChemSusChem ; 10(20): 4080-4089, 2017 10 23.
Article in English | MEDLINE | ID: mdl-28834635

ABSTRACT

In this work, the effects of the formulation of silicon-based composite anodes on their mechanical, storage, and electrochemical properties were investigated. The electrode formulation was changed through the use of hydrogenated or modified (through the covalent attachment of a binding additive such as polyacrylic acid) silicon and acetylene black or graphene sheets as conducting additives. A composite anode with a covalently grafted binder had the highest elongation without breakages and strong adhesion to the current collector. These mechanical properties depend significantly on the conductive carbon additive used and the use of graphene sheets instead of acetylene black can improve elongation and adhesion significantly. After 180 days of storage under ambient conditions, the electronic conductivity and discharge capacity of the modified silicon electrode showed much smaller decreases in these properties than those of the hydrogenated silicon composite electrode, indicating that the modification can result in passivation and a constant composition of the active material. Moreover, the composite Si anode has a high packing density. Consequently, thin-film electrodes with very high material loadings can be prepared without decreased electrochemical performance.


Subject(s)
Electric Power Supplies , Mechanical Phenomena , Silicon/chemistry , Electric Conductivity , Electrochemistry , Electrodes
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