Ratio Of Ions Research Articles

Multi‐Color Magnetic Circularly Polarized Luminescence from Achiral Perovskite (Cs+Pb2+X3) Quantum Dots

AbstractHigh‐performance optoelectronic materials require luminescent materials capable of intense photoluminescence (PL). However, controlling the optical properties of luminescent materials requires complex synthesis and purification procedures. Herein, we propose a simple method for obtaining circularly polarized luminescence from achiral inorganic quantum dots. This method involves applying north‐up and south‐up 1.7 T magnetic fields at 25 °C to five types of achiral antimagnetic perovskite‐Pb‐quantum dots in a solution state. The wavelengths of magnetic circularly polarized luminescence (MCPL) and PL of achiral perovskite‐Pb quantum dots were successfully controlled according to the type and composition ratio of halogen ions. The magnitude of MCPL, gMCPL, was on the order of |gMCPL|=10−3 in a wavelength range of 406–697 nm. Although the perovskite‐Pb‐quantum dots were achiral, the rotation direction of the MCPL could be controlled by varying the direction of the applied magnetic field.

Isotopic Depletion Increases the Spatial Resolution of FPOP Top-Down Mass Spectrometry Analysis.

Protein radical labeling, like fast photochemical oxidation of proteins (FPOP), coupled to a top-down mass spectrometry (MS) analysis offers an alternative analytical method for probing protein structure or protein interaction with other biomolecules, for instance, proteins and DNA. However, with the increasing mass of studied analytes, the MS/MS spectra become complex and exhibit a low signal-to-noise ratio. Nevertheless, these difficulties may be overcome by protein isotope depletion. Thus, we aimed to use protein isotope depletion to analyze FPOP-oxidized samples by top-down MS analysis. For this purpose, we prepared isotopically natural (IN) and depleted (ID) forms of the FOXO4 DNA binding domain (FOXO4-DBD) and studied the protein-DNA interaction interface with double-stranded DNA, the insulin response element (IRE), after exposing the complex to hydroxyl radicals. As shown by comparing tandem mass spectra of natural and depleted proteins, the ID form increased the signal-to-noise ratio of useful fragment ions, thereby enhancing the sequence coverage by more than 19%. This improvement in the detection of fragment ions enabled us to detect 22 more oxidized residues in the ID samples than in the IN sample. Moreover, less common modifications were detected in the ID sample, including the formation of ketones and lysine carbonylation. Given the higher quality of ID top-down MSMS data set, these results provide more detailed information on the complex formation between transcription factors and DNA-response elements. Therefore, our study highlights the benefits of isotopic depletion for quantitative top-down proteomics. Data are available via ProteomeXchange with the identifier PXD044447.

Complexation and extraction of trivalent actinides over lanthanides using highly soluble phenanthroline diamide ligands with different side chains

Although phenanthroline diamide ligands have been widely reported, their limited solubility in organic solvents and poor performance in the separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) at high acidity are still clear demerits. In this study, we designed and synthesized three highly soluble phenanthroline diamide ligands with different side chains. By introducing alkyl chains and ester groups, the ligands solubility in 3-nitrotrifluorotoluene is increased to over 600 mmol/L, significantly higher than the previous reported phenanthroline diamide ligands. Based on anomalous aryl strengthening, benzene ring was incorporated to enhance ligand selectivity toward Am(III). Extraction experiments demonstrated favorable selectivity of all the three ligands towards Am(III). The optimal separation factor (SFAm/Eu) reaches 53 at 4 mol/L HNO3, representing one of the most effective separation of An(III) over Ln(III) under high acidity. Slope analysis, single crystal structure analysis, as well as titration of ultraviolet visible spectroscopy, mass spectrometry, and nuclear magnetic resonanc confirmed the formation of 1:1 and 1:2 complex species between the metal ions and the ligands depending on the molar ratio of metal ions in the reaction mixture. The findings of this study offer valuable insights for developing phenanthroline diamide ligands for An(III)/Ln(III) separation.

Reversible phase separation of CO2 responsive microemulsion: Judgment on whether and how regulated by ratio of ion to responsive surfactant concentration

CO2 responsive microemulsion is a promising solvent with diverse applications in various fields including oil exploitation, material synthesis, and metal recovery. The implementation of reversible phase separation becomes important in enabling the reuses of CO2 responsive microemulsion and facilitating the separation of products in these applications. Earlier reports have established that changes in ion concentration within CO2 responsive microemulsion result in reversible phase separation. Ion in CO2 responsive microemulsion is derived from protonation of CO2 responsive substance which is commonly used as surfactant. An increase in ion concentration leads to a decrease in surfactant concentration. In microemulsion, adsorption of surfactants and ions at the oil–water interface is correlated with interface performance, which influence the ability to achieve efficient phase separation. Interfacial tension (IFT) is an important parameter for interface performance. In this work, ratio of ion to CO2 responsive surfactant concentration was defined as ∮. The relationship between IFT and ∮ was investigated through a combination of experiments and molecular dynamic simulation to explore mechanism of reversible phase separation. The results of present study indicated that ∮ was found to play a vital role in either inhibiting or promoting the formation of hydrogen bond network by hydrophilic groups in surfactants. The changes of hydrogen bond network resulted in increase or decrease in IFT, leading to reversible phase separation. This relationship between IFT and ∮ was used as a theoretical guidance to optimize N2/CO2 bubbling time to achieve reversible phase separation. The optimization improved the efficiency of CO2 responsive microemulsion in extracting active components from Rehmannia glutinosa Libosch. leaves, and enhanced sustainability of the microemulsion. The findings of this study could be used to advance the scientific understanding of reversible phase separation, offering theoretical guidance for green and efficient utilization of CO2 responsive microemulsion in extraction of natural products. Ultimately these results could encourage the broader applications of CO2 responsive microemulsion across diverse fields.

Enhancing damping-like efficiency by low-energy mixed ions bombardment

Pursuing enhanced spin–orbit torque (SOT) has become a significant focus for achieving energy-efficient spintronics devices. Researchers have explored different materials, layer engineering, and various post-deposition modification methods to realize higher SOT. Here, we have utilized the bombardment of mixed ions (Ar+ and He+ in various ratios) with 0.6 kV bias voltage to enhance the SOT efficiency in a Pt/Co/W stack. The bombardment modifies the physical properties (magnetic, electric, and structural) due to cascade collision, knocking off atoms (from the surface), and ion implantation. The increased percentage of He+ suppresses the drastic behavior of cascade collisions, and hence, the properties are tunable by changing the gas ratio. We exploited this behavior to design a material stack with enhanced SOT efficiency. We fabricated Hall bars to quantify SOT and observed a 4.5× increase in the effective damping-like efficiency. The efficiency and switching current density in the stack could be tuned by the variation of Ar:He ion ratio and the exposure duration. This study offers an easy route to tune the energy efficiency of spin devices, contributing to the advancement of next-generation spintronics.

Existence of Small-Amplitude Double Layers in Two-Temperature Non-Isothermal Plasma

In the presence of warm negative ions, ion-acoustic small-amplitude monotonic double layers are theoretically investigated in a plasma consisting of warm positive ions, warm positrons, and two-temperature non-isothermal electrons under the variation of the trapping parameters of electrons, concentration of positrons, and mass ratios of heavier negative ions to lighter positive ions by the Sagdeev pseudopotential method. The corresponding double layer solutions are also discussed for the same variation. Consequently, ion-acoustic solitary waves and double layers have been observed in auroral and magnetospheric plasmas with two-temperature electron distributions found in a laboratory, as well as in the space. This paper shows the effects of trapping parameters of electrons, positron concentration, and mass ratios of heavier negative ions to lighter positive ions on the Sagdeev potential function ψ(φ) and double layer solutions φDL for small-amplitude monotonic double layers. The results are presented graphically in Figs. 1 to 6.

Investigation on plasma ionization process of a micro-cathode arc thruster

Micro-cathode arc thrusters (μCATs) are space propulsion options suitable for microspacecraft, and have recently attracted much attention because of their low electrical power requirements and simple, compact propellant systems. The plasma ionization process, however, is not currently well understood. In this study, a μCAT prototype was designed with the use of different specific materials for each component, enabling the study of the ionization process from the emissive light of excited and ionized states from different elements. ICCD emission spectroscopy and scanning monochromator measurements are conducted inside the electrode channel of a μCAT with a coaxial configuration. The excited state atomic spectral results and ionization state spectral results give us a comprehensive understanding of the behavior of neutral particles and ions during the discharge process of the μCAT. The ionization sequence follows in the order of C+, Al+, Ti+, Cu+, and Ti2+. From the duration of the spectral lines, C I has the shortest duration (16.9 μs), which shows that the ablation of the conductive film is mainly concentrated during the first half of the discharge, while anode and cathode ionization occur over the entire discharge duration. Additionally, Al+ ionization is observed during the discharge process, showing that part of the discharge energy is expended in ionizing the thruster outer shell, resulting in efficiency loss. An ionization ratio of k is proposed in this work to represent the relative ionization of the conductive film and cathode material, aiding us in determining the optimal operation conditions for lifetime extension.

Characterization of Dominant Hydrogeochemical Processes in Groundwater in Onitsha Area, Southeastern Nigeria

The characterization of the dominant hydrogeochemical processes in groundwater in Onitsha area, southeastern Nigeria was carried out. This is to identify the dominant mechanisms responsible for the evolution and the chemical composition of the water sources. A total of fifteen (15) groundwater samples were collected from different locations in the study area in August 2022 and these samples were subjected to chemical analysis using standard methods. The results indicated that the water quality parameters were within the World Health Organization acceptable limits for drinking quality although turbidity in six of the samples exceeded the guideline values. The hydrochemical facies were determined using various plots. Piper diagrams indicated that Ca2+ - Mg2+ - Cl- – SO42- was the dominant facies with Ca2+ and Cl- as the dominant ions. The Durov diagram indicate recharge water in limestone and sandstone aquifers and influenced by important ion exchange reactions. However, the Gibbs plots mainly plotted in the rock dominance zone indicating that the major processes controlling water chemistry in the study area were water-rock interaction and dissolution of rock minerals. The ionic ratio plots were employed to determine the mechanisms and reactions prevalent in the study area that influenced the water chemistry. Na/Cl plot indicated that the excess of Cl- over Na+ was balanced by Ca2+ and Mg2+ while the depletion of Na+ with respect to Clindicated ion exchange reaction which could be attributed to silicate weathering confirming the Na/Cl plot conclusions. The relative abundance of anionic facies shows that Cl- + SO42- were more abundant than HCO3- and the plot of Ca2+ + Mg2+ ions against HCO3- ions depict samples with excess Ca2+ + Mg2+. However, Ca2+ +Mg/HCO3 ratio was less than one (<1) and indicated fresh recharge water.

Uniformity optimization of ion beam sputtering coating equipment based on strong current ion source

The widespread application of ion beam sputtering coating, especially in optical devices, requires the improvement of beam current intensity and uniformity of large-area uniform coatings. The advent of high current Penning sources offers a potential solution. This study introduces an automated optimization simulation method based on a three-electrode extraction system to investigate its influence on ion beam quality and uniformity. Focusing on high current intensity and uniformity, our simulation explores the effects of plasma electrode, inhibition electrode, and extraction electrode angles and distances on ion beam performance. Evaluation metrics include average beam intensity density, average energy of a single particle, and reciprocal variance of each macro particle position, which are achieved through normalization functions, allowing comprehensive comparison of simulation results. To assess coating efficiency, we estimate sputtering yield and depth. The study identifies patterns among electrodes and emphasizes the influence of different ion ratios on beam extraction. The results indicate that optimizing the angle of the plasma electrode and the distance of the suppressed electrode yields a highly uniform ion beam for low charge ions. However, for highly charged ions, similar optimization will reduce the current strength, so compensation needs to be achieved through electrode shape optimization. This research provides a model for systematically optimizing the three-electrode extraction system, guiding researchers in achieving optimal solutions based on ion source characteristics and application requirements. Additionally, we introduce a method of estimating the sputtering depth of mixed ion beams. This study provides valuable insights for advancing ion beam sputtering coating technology and reference for making the decision on design and application of ion source.

Fabrication of well-aligned Co-MOF arrays through a controlled and moderate process for the development of a flexible tetrabromobisphenol A sensor.

Tetrabromobisphenol A (TBBPA) has attracted a great deal of attention due to its side effects and potential bioaccumulation properties. It is of great importance to construct and develop novel electrochemical sensors for the sensitive and selective detection of TBBPA. In the present study, cobalt (Co) based metal-organic frameworks (MOFs) were synthesized on carbon cloth (CC) by using cobalt nitrate hexahydrate and 2-methylimidazole. The morphological characterization was carried out by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The results showed that Co-MOFs/CC have a leaf-like structure and abundant surface functional groups. The electrochemical properties of the sensor were investigated by differential pulse voltammetry (DPV). The effects of different ratios of metal ions to organic ligands, reaction temperature, time, concentration, pH value of the electrolyte, and incubation time on the oxidation peak current of TBBPA were studied. Under the optimal conditions, the linear range of the designed sensor was 0.1 μM-100 μM, and the limit of detection was 40 nM. The proposed sensor is simple, of low cost and efficient, which can greatly facilitate the detection tasks of environmental monitoring workers.

Bi-doped ZnAl-layered double hydroxides with enhanced photocatalytic activity for ciprofloxacin degradation: the synergistic effect of Bi doping and oxygen vacancies

In this study, a series of Bi-ZnAl-LDHs (BZA-X) enriched with oxygen vacancies (OVs) were synthesized by doping ZnAl-LDHs with different ratios of bismuth ions.

Mid-infrared passive spectroscopic imaging for visualizing tooth quality.

Although the measurement of tooth quality is necessary for precise prediction of caries formation, typical measurement methods include tooth-hardness measurements and absorption spectroscopy, which generally use infrared light irradiation. These methods are destructive or invasive, and obtaining two-dimensional information in the oral cavity is difficult. Mid-infrared emissions from the surface of an object reflect intrinsic vibrations of molecules in the object. In this study, a mid-infrared passive spectroscopic imaging system was developed using an inexpensive uncooled microbolometer array sensor with an optimized multi-slit, which eliminated the cancellation of interference intensities between two adjacent emission points, to obtain two-dimensional information from an object without external infrared light irradiation. First, the feasibility of obtaining two-dimensional information on tooth quality using the proposed system was examined, and emission spectra attributed to phosphate ions in hydroxyapatite (HAp), the main component of enamel, were successfully obtained from bovine teeth. Further, the hardness of bovine teeth was measured, and a correlation (R2 = 0.8067) between the Vickers hardness and peak area ratio of phosphate ions assigned to the crystalline and amorphous phases of a tooth was established. Additionally, tooth-hardness visualization in a non-contact manner was demonstrated as two-dimensional information using the obtained regression equation.

Ion current rectification properties of non-Newtonian fluids in conical nanochannels.

Ionic current rectification generated by the geometric asymmetry of conical nanochannels has gradually attracted attention, but most studies have been limited to Newtonian fluids. In this study, the ionic current rectification characteristics in conical nanochannels filled with non-Newtonian fluids are investigated by numerical simulations. Electroosmotic flow and ion transport in Sisko fluids are solved using the Poisson-Nernst-Planck equations and the Navier-Stokes equations. The effects of the Debye parameter, power-law indexes and applied voltage on the ionic current, axial potential, ion concentration, radial velocity and rectification ratio in the nanopores are investigated. When κRt = 1, the current rectification ratio increases with the increase of the power-law index. However, when κRt = 6, the current rectification ratio first increases and then decreases with the increase of the power law index, reaching the maximum value at n = 1.0. These findings have positive implications for the construction of some nanodevices such as nanofluidic diodes.

New insights into the effects of small permanent charge on ionic flows: A higher order analysis.

This study investigated how permanent charges influence the dynamics of ionic channels. Using a quasi-one-dimensional classical Poisson-Nernst-Planck (PNP) model, we investigated the behavior of two distinct ion species-one positively charged and the other negatively charged. The spatial distribution of permanent charges was characterized by zero values at the channel ends and a constant charge $ Q_0 $ within the central region. By treating the classical PNP model as a boundary value problem (BVP) for a singularly perturbed system, the singular orbit of the BVP depended on $ Q_0 $ in a regular way. We therefore explored the solution space in the presence of a small permanent charge, uncovering a systematic dependence on this parameter. Our analysis employed a rigorous perturbation approach to reveal higher-order effects originating from the permanent charges. Through this investigation, we shed light on the intricate interplay among boundary conditions and permanent charges, providing insights into their impact on the behavior of ionic current, fluxes, and flux ratios. We derived the quadratic solutions in terms of permanent charge, which were notably more intricate compared to the linear solutions. Through computational tools, we investigated the impact of these quadratic solutions on fluxes, current-voltage relations, and flux ratios, conducting a thorough analysis of the results. These novel findings contributed to a deeper comprehension of ionic flow dynamics and hold potential implications for enhancing the design and optimization of ion channel-based technologies.

Etching-induced ion exchange engineering of two-dimensional layered NiFeCo-based hydroxides for high energy charge storage.

Efficient and rapid synthesis of transition metal-based hydroxides with tailored microstructures has emerged as a promising approach to fabricate high-performance electrode materials for energy storage devices. However, many conventional synthesis methods are cumbersome, expensive and time-consuming, and the microstructures of electrode materials are usually uncontrollable. Herein, we propose a fast and cost-effective approach to electrochemically in situ grow NiFeCo-based ternary hydroxides (NiFeCo-THs) with layered nanosheet structures on pretreated nickel foam (NF). The in situ grown NiFeCo-THs were in direct contact with the NF to form a monolithic electrode as NiFeCo/NF. By engineering the ion exchange process for controlling the ionic ratio, the monolithic Ni1(Fe/Co = 1/1)0.5/NF electrode was fabricated and found to show the optimum electrochemical behavior with a specific capacitance of 2.32 C cm-2 at 2 mA cm-2 as a result of its characteristic microstructures. Furthermore, a hybrid supercapacitor was constructed utilizing the monolithic Ni1(Fe/Co = 1/1)0.5/NF electrode and activated carbon as the cathode and anode, respectively, and it was found to have an energy density of 81.1 μW h cm-2 at a power density of 808.8 μW cm-2. After 5000 cycles, 84.0% of the initial capacitance of the hybrid supercapacitor was maintained, and the monolithic Ni1(Fe/Co = 1/1)0.5/NF electrode still retained the arrayed nanosheet structure.

The implication of the hydrogeochemical processes for groundwater chemistry in a semi-arid region: A case study of the Bokoya massif (Central Rif, Morocco)

Natural and anthropogenic factors control groundwater chemistry in the semi-arid area in northern Morocco called Bokoya massif. The main goal of this study was to evaluate the geochemical processes that affected groundwater mineralization in the Bokoya massif. As a result, In April 2016, sixty-one (61) water samples were collected from various locations, including wells and springs throughout the Bokoya massif, and analyzed for physicochemical parameters using standard methods. The descriptive study of the physicochemical parameters revealed that the waters were neutral to slightly basic (pH values range between 7,16 and 8,5) and moderately to strongly mineralized (TDS values range between 555,20 and 7980,10 mg/l). Sodium chloride was the dominant hydrochemical facies in the groundwater of the study area, with a percentage reaching (80%) noting the minority of magnesium bicarbonate facies and the absence of sodium bicarbonate and chlorinated calcium type. The tests of the ionic ratio (Cl- /Na+, Cl-/HCO3- versus Cl-, Ca2+/Mg2+, Ca2+/SO4-, Ca2+/Mg2+ versus Cl-, (Ca2+ Mg2+)/ HCO3-), indicate that the order of the dominant cations is Na+ >Ca2+>Mg2+>K+ and of the dominant anions is Cl- >HCO3->SO42-. It suggests that the dominant factors controlling water chemistry are rock dissolution and evaporation, silicate weathering, and ion exchange. Gibbs diagram defines the relationship between water chemistry and the lithology of the aquifer. It showed that most of the groundwater composition in this area is linked to the geochemical processes of evaporation and crystallization, and carbonates and silicate alteration control the minority.

Effect of V/Mo Atomic Ratio on the Microstructure and Mechanical Properties of MoVCuN Coatings.

To improve the gas ionization ratio, the Mo-V-Cu-N coatings were deposited by pulsed dc magnetron sputtering with assistance from an anode layer ion source, and the influence of the V/Mo atomic ratio was explored with regard to the microstructure and mechanical properties of the coatings. The findings of this study indicated that the MoVCuN coatings exhibited a solid solution phase of FCC B1-MoVN with a prominent (220) preferred orientation, and the deposition rate was found to decrease from 4.7 to 1.8 nm/min when the V/Mo atomic ratio increased. The average surface roughness of the MoVCuN coatings gradually decreased, and the lowest surface roughness of 6.9 nm was achieved at a V/Mo atomic ratio of 0.31. Due to the enhanced ion bombardment effect, the coatings changed from a coarse columnar to a dense columnar crystal structure, and promoted grain refinement at higher V/Mo atomic ratios, contributing to a gradual improvement in the compressive residual stress, hardness and adhesion strength of the coatings.

Hydrochemical characterization and water quality perspectives for groundwater management for urban development

The present study was conducted to assess groundwater quality for drinking and industrial water purposes, evaluate the driving mechanisms of groundwater chemistry, and suggest appropriate management measures to protect groundwater resources for sustainable urban development in a part of Odisha, India. Overall Water Quality Index (OWQI) and Industrial Water Quality Index (IWQI), geochemical ratios and chemometric analyses were used to identify the causes of ionic sources of natural and anthropogenic inputs. Groundwater samples were collected and analysed for chemical parameters. The OWQI indicated that 95.93% of the study region is unfit for drinking water purposes due to high concentrations of Mg2+, Na+, Cl−, SO42−, NO3−, and F− ions supported by the ANOVA test. The IWQI found corrosion and incrustation activities in 80.05% and 94.33% of the study region, respectively, which hinders urban development. The trilinear diagram illustrated that the freshwater type changes completely to mixed water type, and then to reverse ion exchange water and saline water types due to the influence of anthropogenic sources. Gibbs diagrams explaining the mechanisms responsible for groundwater chemistry that groundwater quality moves from the rock domain to the evaporation domain due to human-induced activities. Saturation indices showed that fluoride, gypsum, and halite are in a dissolved state, and calcite is in a precipitated state. Different ionic ratios clearly illustrated that groundwater quality is mainly modified by anthropogenic sources from lithological origin. Principal component analysis (PCA) classified the chemical parameters into salinity, alkalinity, and soil-controlled factors of groundwater chemistry based on their high-positive loadings. High positive scores of PCA, and Clusters 1 and 2 of the hierarchical cluster analysis clearly differentiated polluted and unpolluted affected groundwater samples. Therefore, it is suggested to take appropriate preventive measures to improve the groundwater resources. Otherwise, there will be adverse conditions for urban activities.

Corrosion resistance of cerium-doped Pb-Co alloy coatings in seawater

A luminum and its alloys, known for low density and high tensile strength, are widely used in marine equipment but prone to corrosion. This study aims to enhance their corrosion resistance by developing cerium-modified hydrophobic Pb-Co coatings through one-step electrodeposition. Adjusting the cerium to cobalt ion ratio optimized the coatings for superior resistance to wetting and corrosion. The research investigates physicochemical properties, wetting behavior, adhesion strength, and corrosion performance of these coatings on aluminum. Mechanisms of deposition and corrosion resistance are explained through experimental results, analytical insights, and DFT calculations, advancing our comprehension of corrosion protection in cerium-modified Pb-Co coatings.

Hydrochemistry, controlling mechanisms and water quality index in hot springs of the Kullu-Manali region, India

The present study highlights the unique chemical characteristics of hot springs and their comparison with cold springs, surface water, and groundwater in the same area. The hot springs' temperature ranges from 27 to 96 °C, which induce variable degree of hydrochemical alteration of hot springs' water. The concentrations of Na+ and K+ are highly correlated with Cl−, HCO3−, and SO42− in hot springs, while Ca2+ and Mg2+ behave erratically. The Na/Cl ionic ratios give clues of a restricted geological environment of thermal waters, mixing in cold springs and groundwater, and a meteoric origin of the surface water. The SiO2 behave conservatively, with little change in different water types except surface water. The concentrations of SiO2, highest in the hot springs and lowest in the surface water, help draw depth profiling of different water types. Mixing of ascending hot springs with overlying waters of different origins creates ambiguity in chemical interpretations. Due to mixing with different water types, Chalcedony thermometry better represents hot springs than Na–K–Mg geothermometry. As a result, hot springs alter from Na–Cl and Na–Cl–SO4 type facies with high SiO2 and gradually evolved in Ca–Mg–Na–HCO3–Cl type water. Similarly, most cold springs show mix-type and Ca–HCO3 water types. The chemical characteristics of cold springs are similar to groundwater and equally sensitive to seasonal variation due to mixing with meteoric recharge. The surface water is characterized by Ca–Cl2 type water. All water types acquire unique chemical signatures due to the combined effect of geological formations, depth, temperature, degree of meteoric recharge, and, to some extent, anthropogenic pollution. The Water Quality Index (WQI) assessment revealed that three samples from the Kullu and Kalath regions fall in poor WQI, requiring immediate protection from anthropogenic pollution.