K1 K2 Research Articles

Experimental study of materials for the filtration of the intake air of the internal combustion engine of a motor vehicle

Experimental evaluation of the properties of filter materials in the selection of material for filtration of inlet air of internal combustion engines was carried out. The filtration characteristics were determined: filtration efficiency and accuracy, as well as flow resistance depending on the dust mass load. Filter materials based on cellulose, polyester, microfiber glass, and cotton and polyester nonwoven beds were studied. Two filter beds consisting of three base filter materials were designed: composite K1 (polyester-microglass-cellulose) and composite K2 (cellulose-microglass-cellulose), and their characteristics were performed. The air filtration quality factor was used to analyze the test results. The coefficient of filtration efficiency was defined, showing the effect of the preliminary stage on the total time of the filtration process. It was shown that the K1 composite has high (dpmax = 1.5÷3 µm) filtration accuracy, high initial filtration efficiency (99.8%), which shortens the pre-stage, and extends to 96-98% the duration of the main stage of the filtration process. The K1 composite obtained more than twice the mass loading of dust (kdK1 = 148,9 g/m2), which will allow the vehicle's mileage to be extended.

Mechanical properties and gas permeability of silica-gel modified hydratable magnesium carboxylate bonded refractory castables in drying process

The hydratable magnesium carboxylate (HMC) bonded castables have a high-level gas permeability while the mechanical strength decreased sharply during drying process. Silica-gel with high activity is a porous structure after drying and can potentially increase the intermediate-temperature strength without reducing the gas permeability of the castables. In this study, the mechanism of silica-gel modified the HMC, and the effects on the properties of the castables were investigated. The surface of the hydration products of HMC is covered with a thin protective layer of siloxane network. The proportion of fine permeable pores (0.1 μm ∼1 μm) increased, optimizing the connected network channels in the castables. Compared to the pure HMC bonded castables, with the HMC/silica-gel mass ratio of 2, the cold modulus of rupture of the castables increased by 2 times after heat treatment in the range of 400 °C ∼600 °C. Especially, the permeability constants Darcian k1 and non-Darcian k2 increased by 37 times and 38 times after heat treatment at 600 °C, respectively.

Comparison of intubating conditions in supine (sniffing) and 25° back-up position using channelled and non-channelled video laryngoscopes - A randomised controlled study.

The 25°back-up position is proposed to increase the efficacy of preoxygenation and provide better tracheal intubating conditions when using a direct laryngoscope. This study aimed to compare the ease of tracheal intubation between supine and 25° back-up positions when using two video laryngoscopes (VLS). One hundred adults with normal airways and belonging to the American Society of Anesthesiologists physical status classes I and II, requiring general anaesthesia, were randomised in groups K and M. The trachea was intubated using King Vision and McGrath VLS in either supine (groups K1 and M1) or 25° back-up (groups K2 and M2) positions. The 25° backup position was given by raising the operating table from the horizontal position by flexing the torso at the hips so that an imaginary line connected the patient's external auditory meatus to the sternal notch. Modified Intubation Difficulty Scale (mIDS) was the primary outcome, and intubation time, the number of intubation attempts, vital parameters, and complications were compared secondarily. Statistical analysis was done using MedCalc software by applying an independent t-test for parametric data and a Chi-square test for categorical data and finding the risk ratio. Mean (Standard deviation) mIDS was significantly reduced using both VLS in the 25° back-up position [0.92 (0.75) versus 0.48 (0.58), P = 0.025, degree of freedom (DF): 48, mean difference (95% confidence interval [CI]):-0.44 (-0.821 to - 0.059) in group K1 versus group K2 and 0.76 (0.59) versus 0.36 (0.48), P = 0.012, DF: 48, mean difference (95% CI): -0.40(-0.706 to - 0.094) in group M1 versus group M2, respectively]. The risk ratio comparing both the positions for the total number of patients requiring manoeuvres during intubation using both the VLS was 0.48 with P = 0.0004 and 95% CI = 0.305 - 0.765. Intubation time was shorter in the 25° backup position by using King Vision (P = 0.005) and McGrath (P = 0.042) VLS. The 25° backup position helps provide ease of intubation using both the channelled (King Vision) and non-channelled (McGrath) VLS.

Analysis of vitamin K1 and major K2 variants in rat/human serum and lipoprotein fractions by a rapid, simple, and sensitive UHPLC-MS/MS method

Determination of the various forms of vitamin K, which are involved in coagulation and other physiological processes in humans, is challenging and no standardized method is yet available. Therefore, a reliable and practical method was developed to quantify vitamin K levels in serum and additionally in lipoprotein fractions to clarify its distribution. The LC-MS/MS method for the determination of vitamin K1 and the three main isoforms of vitamin K2 (MK-4, MK-7, MK-9) was combined with a gradient ultracentrifugation technique to allow the separation of lipoprotein fractions. The chromatographic separation was carried out on a Kinetex™ C18 column using a mobile phase consisting mainly of methanol. The target analytes were detected by electrospray ionization mass spectrometry. The separation of all four substances was achieved after a simple sample preparation technique based on miniaturized liquid-liquid extraction. Our method of only 8.5 min revealed the levels of the major forms of vitamin K in 59 human and 12 rat sera and confirmed our hypothesis that vitamin K is primarily (about 50 %) found in the high-density lipoprotein fraction. The median concentrations of vitamin K1, MK-4, MK-7, and MK-9 were found to be 1.19, 2.98, 0.43, and < 0.71 nmol/L in human serum and 1.74, 6.75, less than 0.2, and less than 0.5 nmol/L in rat serum, respectively.

A new method for predicting the maximum wave height of ship-generated onshore slopes in restricted channel

The ship-generated wave causes erosive damage to the slopes of inland waterways and confined waters such as the coastal zone. This critical issue is essentially associated with the navigational safety and sustainable development of coastlines, so it is vital to predicting the maximum wave height of the ship-generated wave (Hm) in the coastline of confined waters. The prediction equations of prior research works are mostly based on measured data and multiple regression analysis; however, this paper aims to propose a novel methodology to predict the maximum wave height of ship-generated waves in confined waters. The maximum wave height caused by a self-propelled ship under various conditions with confined water is measured by employing a water flume. Furthermore, the relationships of functions in the prediction model equation are appropriately derived by dimensional analysis, and the prediction equation model is then solved via the particle swarm optimization algorithm (PSOA). The experimental results reveal that the maximum wave height of the ship-generated wave is seriously affected by the water depth of the channel (hc), the navigation speed of the ship (Vc), and the distance from the forecast point to the navigation line of the ship (Sc). In addition, the maximum wave height grows and then lessens, which touches its peak point in the region close to Frh = 1. The dimensionless analysis indicates that the large wave height of the ship-generated wave can be expressed as a function of the channel depth (hc), ship speed (Vc), and the distance from the measurement point to the ship’s navigation line (Sc) as; HmSc=1Frh2f(gScVc 2). Subsequently, the specific prediction equation is determined by a regression model according to the measured data under various working conditions. By adopting the model expression equation, namely, HmFrh2Sc=k1(gScVc 2)k2, the coefficients k1 and k2 are evaluated via the PSOA, and the relationship between the water depth of the channel and the coefficients is suitably outlined to obtain the maximum wave height prediction model equations for ship-generated waves.

Corneal parameters, ocular biometers, and retinal and choroidal thickness in acromegaly patients

BackgroundTo compare ocular findings of acromegaly patients with healthy individuals and investigate the relation of serum levels of insulin-like growth factor (IGF-1) along with growth hormone (GH) and pituitary tumor (adenoma) dimensions (TD) with specific ocular parameters. MethodsThe ocular parameters of acromegaly patients (n = 38) were compared with those of healthy subjects (n = 36). These parameters were intraocular pressure, keratometric (K1–K2) values, central corneal thickness (CCT), total axial length along with anterior chamber-lens-vitreous length, retinal nerve fiber layer (RNFL) thickness, central foveal thickness (CFT), choroidal thickness (CT), ganglion cell layer thickness (GCLT), and inner plexiform layer thickness (IPLT). Also investigated was whether there was a correlation between disease duration, TD, GH, IGF-I, CCT, RNFL, CFT, GCLT, IPLT, and CT. ResultsThe lens length of the acromegaly group was increased (p = 0.014). GH and IGF-1 levels were positively correlated with CT and CCT, respectively (p = 0.041, r = 0.343) (p = 0.03, r = 0.347). Analysis of TD also found a highly negative correlation with the mean RNFL thickness of the acromegaly patients (p < 0.01, r = -0.603). The mean value of the inner parts of GCLT and IPLT was negatively correlated with TD (p = 0.041, r = -0.343 and p = 0.025, r = -0.379, respectively). ConclusionSerum IGF-1 and GH levels might be determinant factors in CCT and CT, respectively. The pituitary adenoma size increasing may be prone to lead RNFL, ganglion cell layer, inner plexiform layer thinning. Increased lens thickness was found in the acromegaly group.

Characterizing ancient jade by on-site analysis in Sanxingdui, China

Characterized by various materials, types and patterns, ancient jade is a unique symbol of Chinese civilization. However, crucial information can be jeopardized by the sudden exposure during excavations, and abundant jade artefacts were stored without scientific identification in the archaeological context. Sanxingdui site was an essential center of a complex society in the Chengdu Plain in Bronze Age China. During the new excavation in Sanxingdui sacrificial area (pit K3–K8) since 2019, cabins have been used for better site conservation, providing ideal conditions for on-site study. Employing portable devices, on-site non-destructive analysis were conducted inside pit K8. The results of Raman and XRF show that the raw material is nephrite, indicating the consistency of jade material preference with the majority of Sanxingdui jade from pit K1–K2 and the majority of prehistoric jade as well. Evidence of mineral thermal phase transition from tremolite to diopside was found on the zao chisel and proved the existence of jade burning related to the sacrificial activities. The Fe content in the surrounding soil led to the red and orange colors on the jade surfaces and the neutral environment helped retaining of the original texture and natural luster of the nephrite. Based on the geometric morphometric database, the jade zhang forked blade was quantitatively recognized as the most typical zhang type only found in Sanxingdui. It is demonstrated that the non-destructive analysis is efficient to characterize the ancient jade and makes it possible to construct the database of all the jade artefacts on site, providing the basis of solving larger-scale archaeological problems that are not necessarily bounded by geographical regions or time periods.

Insight into the adsorption thermodynamics, kinetics, and photocatalytic studies of polyaniline/SnS2 nanocomposite for dye removal

The study aims to address the synthesis, the kinetics of adsorption, and photocatalytic application of Polyaniline/tin sulfide (PANI/SnS2) nanocomposite against brilliant blue (BB) dye. PANI/SnS2 was prepared by in-situ polymerization of the aniline to which hydrothermally synthesized SnS2 was added. Adsorption thermodynamics and kinetics of PANI/SnS2 were discussed against the BB dye using Langmuir and Freundlich adsorption isotherm. Maximum adsorption capacity (qm) and adsorption equilibrium constant (K) were found to be 165.2 mg g−1, and 0.027 min−1. Moreover, Adsorption kinetics were studied by the pseudo-first and second-order reactions. The adsorption rate constant k1 and diffusion rate constant k2 were found to be 0.1274 and 0.0233 min−1. PANI and SnS2 with tunable band gap energy, adsorption, and redox property exhibited excellent activity towards the photodegradation of BB dye. The effect of heterojunction between PANI/SnS2 was observed by an increased rate of transfer of electrons. The rate constant was highest in the case of PANI/SnS2 (20%), which is 0.0172 min−1 and a maximum of 96.2% of BB dye was degraded in 45 min. The hydroxyl (•OH) and superoxide (•O2−) radicals were generated during photocatalysis that degrades the BB dye into nontoxic products, which were confirmed by the trapping experiment. The obtained results indicate the excellent adsorption and photocatalytic activity of PANI/SnS2 nanocomposite.

The Effect Various of Kinds Organic Fertilizer On Gaharu Seedling (Aquilariamalaccesis LAMK) In The Field

This research aims to determine the effect of various types of organic fertilizer on the growth of agarwood seedlings (aquilaria malaccensis lamk). This research was conducted in August to November 2022. This study was conducted at Arboretum of the Faculty of Forestry. Tadulako University Palu. This research uses a complete random design (RAL) consisting of 3 treatments namely K1 (Control) K2 (DOAMI Organic Fertilizer) K3 (Gresik Organic Fertilizer). The results showed that the administration of various types of organic fertilizer had a significant effect on high increase and seedling diameter, but did not significantly affect the increase in the number of leaves. K2 treatment gives better results than other treatment. Average of seed height K1 = 4.5, K2 = 7.75 k3 = 6.75, the average increase in the diameter of the seedlings is K1 = 0.37 K2 = 0.72 k3 = 0.45. The average increase in the number of leaves of K1 = 6, K2 = 10.25, K3 = 7.75.

THE CALCULATION OF THE BUILDING STRUCTURE OF INSTITUT TEKNOLOGI DAN BISNIS SABDA SETIA KOTA PONTIANAK

The publishing of the new Indonesian seismic code SNI-1729-2019, which was just issued at the end of 2017, is one example of how laws controlling building construction have been changed to keep up with the times, which is the earth study result by Pusat Studi Gempa Nasional (PUSGEN) update includes incorporating a new source of an earthquake, new active faults, more accurate topography map, and earthquake catalog. One of the new seismic zones in the SNI is Pontianak, so in planning buildings in Pontianak, earthquake force parameters must be calculated so that in the event of an earthquake, anticipatory measures can be taken so as not to cause significant losses. This study is planning the structure of Institut Teknologi dan Bisnis Sabda Setia Kota Pontianak building, which refers to the Indonesian seismic code SNI-1729-2019. The structural analysis is carried out using the help of a structural analysis program adjusted to the value of the planned structural dimensions, which are floor slabs with a thickness of 100 mm, main beams 350/700 mm, child beams 300/600 mm and 250/500 mm, to columns K1 D-800 mm and K2 500×500 mm.

The biological responses of vitamin K2: A comprehensive review.

Vitamin K1 (VitK1) and Vitamin K2 (VitK2), two important naturally occurring micronutrients in the VitK family, found, respectively, in green leafy plants and algae (VitK1) and animal and fermented foods (VitK2). The present review explores the multiple biological functions of VitK2 from recently published in vitro and in vivo studies, including promotion of osteogenesis, prevention of calcification, relief of menopausal symptoms, enhancement of mitochondrial energy release, hepato- and neuro-protective effects, and possible use in treatment of coronavirus disease. The mechanisms of action associated with these biological effects are also explored. Overall, the findings presented here suggest that VitK, especially VitK2, is an important nutrient family for the normal functioning of human health. It acts on almost all major body systems and directly or indirectly participates in and regulates hundreds of physiological or pathological processes. However, as biological and clinical data are still inconsistent and conflicting, more in-depth investigations are warranted to elucidate its potential as a therapeutic strategy to prevent and treat a range of disease conditions.

Determination of Stability Constant of Flurosubstituted Chlconemines for its Medicinal Efficiency

The good activity of drug is depending upon its stability constant i.e. proton ligand stability constant and metal ligand stability constant. If the stability constant is fairly very good then it should use as a good and effective medicine .In content to this in present work the proton ligand stability constant and metal ligand stability constant of fluro substituted chalconeimines L5 = 2-Hydroxy naphthalene 4-dimethyl aniline 4- fluro chalconeimine [FN] are studied with highly reactive transition metal like (Cu (II), Co(II),Cr(II) and Fe(III)). The 70% dioxane water solvent system used in the present investigation. The presence of –OH group confirmed by using of 0.1 M ionic strength. The transition metal (Cu (II),Co (II),Cr(II)and Fe(III)) used and the ligand form 1:1 and 1:2 complex with all values of log k1 and log k2 positive.

Agreement between a new swept-source ocular coherence tomography and a Placido disc-dual Scheimpflug ocular biometric devices.

To evaluate the agreement between two biometry devices, the Heidelberg Anterion and the Galilei G6 Lens Professional. Eyes were scanned with both biometry devices. Analysis of inter-device agreement was conducted for the following metrics: flat (K1), steep (K2) and mean K (Km) for anterior, posterior and total cornea, lens thickness (LT), central corneal thickness (CCT), anterior chamber depth (ACD), white to white (WTW) and axial length (AL). Generalised Estimating Equations were used to account for inter-eye correlation. Bland-Altman analysis was conducted to derive the mean difference (MD) and limits of agreement (LoA) between devices. Differences were deemed clinically significant if they would result in a change in post-operative refraction of 0.25D or more. 159 eyes of 91 patients were included. For the anterior cornea, no significant MD was found for K1 (-0.11D) and K2 (-0.10D), although a significant MD was found for Km (-0.10D). For posterior cornea, while there were no significant MDs between devices, the LoAs were wide for both posterior K1(-0.70, 0.68) and posterior K2 (-1.01, 1.29). For total corneal power, significant MDs were found in K1 (0.36D), and Km (0.26D) but not for K2 (0.17D). Significant MDs were found for LT (0.179mm), CCT (-0.005mm), ACD (-0.111mm) and WTW (-0.158mm), but not for AL (-0.021mm, p > 0.05).Conclusion: There are statistically but not clinically significant differences between Anterion and Galilei G6 Lens Professional in anterior Km, LT, CCT, ACD and WTW. Measurements of the posterior and total cornea are not interchangeable between devices.

Isolation and characterization of salt tolerant bacteria from saline soils of Bangladesh

Salinity is an important abiotic stress that limits the productivity of crops growing on the salt affected areas because excess salt concentration in the soil has detrimental effect on growth and development of plants. Beneficial microorganisms having the inimitable characteristics like tolerance to soil salinity, synthesis of plant growth hormones, facilitating nutrient uptake, bio-control ability and beneficial interaction with plants could be vital to address the problem. An experiment was carried out with the objectives of isolating and characterizing saline tolerant bacteria for utilizing as a tool for bioremediation. Soil samples were collected from three saline affected districts of Bangladesh viz. Khulna, Satkhira and Bhola. The highest bacterial population was found in Satkhira followed by Khulna and the lowest was found in Bhola. Eighteen (18) bacterial isolates viz. BU B1, BU B2, BU B3, BU B4, BU B5, BU B6, BU B7, BU B8, BU B9, BU S1, BU S2, BU S3, BU S4, BU S5, BU S6, BU S7, BU K1 and BU K2 were identified according to the colony color and shape. All the isolated bacteria showed positive response to produce IAA. Isolates BU S4, BU B7 and BU S1 showed highest IAA production ability. Among the 18 isolates, 12 were Gram positive and showed negative reaction on KOH test and the rest 6 isolates were Gram negative and showed positive reaction on KOH test. The isolates BU B1, BU B4, BU B6, BU S6, BU K1 and BU K2 were slow growing bacteria and the rest were fast grower. Biochemical tests indicate that 13 isolates were positive for catalase and P solubilization test. Whereas, 11 isolates could degrade the cellulose. For screening of bacterial isolates against NaCl tolerance, the isolates were cultured on NA medium having different salt concentrations. Experimental results reveal that all the isolates could tolerate 4.0% NaCl concentration except BU B6. Ten isolates showed the ability to tolerate NaCl up to 8.0%. The isolates BU B7 and BU S4 showed highest salinity tolerance along with better response to different biochemical characteristics. Therefore, these isolates may become promising for the bioremediation of soil salinity in the saline affected areas of Bangladesh.

RESPONS TANAMAN KACANG HIJAU (Vigna radiata. L) TERHADAP PEMBERIAN AMELIORAN KATION POLIVALEN Cu2+, Fe3+, Zn2+ DAN KOMPOS PELEPAH KELAPA SAWIT PADA MEDIA GAMBUT

The purpose of this study was to determine the response of mung bean to the application of ameliorant polyvalent cations Cu2+, Fe3+, Zn2+ and Palm Oil Midrib Compost Fertilizer on Peat Media. The research was carried out in the experimental farm of the Faculty of Agriculture, Riau Islamic University, Pekanbaru from March to May 2020. The design used in this study was a factorial completely randomized design consisting of two factors. The first factor is the provision of ameliorant material (A) consisting of 4 levels of A0 (without ameliorant), A1 (Cu2+), A2 (Fe3+), and A3 (Zn2+) and the second factor is the provision of palm frond compost (K) consisting of 4 levels of K0 ( without compost) K1 (12 g/plant) K2 (24 g/plant) K3 (36 g/plant). Observational data were analyzed statistically and further test BNJ level 5%. The results of the study by interaction gave an influence on the observation of seed weight per plant, with the best treatment being the provision of ameliorant Cu2+ and oil palm midrib compost 24 g/plant (A1K2). The main effect of giving ameliorant material gave effect on all observation parameters, namely plant height, relative growth rate, speed of dry matter filling, effective seed filling time, flowering age, harvest age, seed weight per plant, percentage of empty pods, the weight of 100 seeds and root volume, where the best treatment is in the provision of ameliorant Cu2+ (A1). The main effect of oil palm midrib compost affects the observation parameters, namely plant height, relative growth rate, speed of dry matter filling, flowering age, harvest age, seed weight per plant, percentage of empty pods, weight of 100 seeds and root volume where the best treatment is in giving 24 g/plant (K2) of oil palm midrib compost.

Emergence of K1 ST23 and K2 ST65 hypervirulent klebsiella pneumoniae as true pathogens with specific virulence genes in cryptogenic pyogenic liver abscesses Shiraz Iran.

Hypervirulent Klebsiella pneumoniae (hvKp) pathotype is emerging worldwide in pyogenic liver abscesses (PLAs). However, the role of virulence factors in pathogenicity remains unclear. On the other hand, the epidemiology of PLAs in Iran is unknown. From July 2020 to April 2022, bacterial species were isolated and identified from the drainage samples of 54 patients with PLAs. K. pneumoniae as the most common pathogen of pyogenic liver abscesses was identified in 20 (37%) of the 54 patients. We analyzed the clinical and microbiological characteristics of K. pneumoniae-related pyogenic liver abscesses. Antibiotic susceptibility testes and string test were performed. 16S rRNA, antibiotic resistance, and virulence genes were determined by polymerase chain reaction amplification. Clonal relatedness of isolates was identified by multilocus sequence typing. Virulence levels were assessed in the Galleria mellonella larval infection model. Four hvKp isolates (K1/K2) were found to be responsible for cryptogenic PLAs, and 16 classical K. pneumoniae isolates (non-K1/K2) were associated with non-cryptogenic PLAs. Three capsular serotype K1 strains belonged to sequence type 23 (ST23) and one K2 strain to ST65. Meanwhile, the non-K1/K2 strains belonged to other STs. ST231 was the most common strain among the classical K. pneumoniae strains. Compared with the non-K1/K2 strains, capsular serotypes K1/K2 strains were less resistant to antibiotics, had positive string test results, and had more virulence genes. In Galleria mellonella, a concentration of 106 colony-forming units of the K1 hvKp strain resulted in 100% death at 24 hours, confirming the higher virulence of the hvKp strain compared with cKp. K. pneumoniae isolates represented that the acquisition of any plasmid or chromosomal virulence genes contributes to pathogenicity and high prevalence in PLAs. Meanwhile, hvKp isolates with a specific genetic background were detected in cryptogenic PLAs.

Comparison of accelerated corneal cross-linking for progressive keratoconus in pediatric and adult age groups: One-year results

To compare one-year results of accelerated cross-linking (ACXL) treatment for progressive keratoconus in pediatric and adult age groups. The records of patients who had undergone the ACXL procedure (9mV/cm2, 10min) for progressive keratoconus were evaluated retrospectively. The patients were divided into 2 groups, with the pediatric group aged 17years or less and the adult group aged 18years or more, for the statistical analysis. Pre- and 12-month post- ACXL best-corrected visual acuity (BCVA), maximum keratometry (Kmax), sim K1, sim K2, corneal thickness at the thinnest point (thCT), and corneal astigmatism (CA) values of the patient groups were recorded. Thirty-two right eyes of 32 patients were included in the pediatric group, and 32 right eyes of 32 patients were included in the adult group. A significant improvement in BCVA and a significant decrease in thCT values were present in both groups 12months after the surgery compared to the preoperative period. The decrease in Kmax, sim K1 and sim K2 values compared to the preoperative period was significant in the adult group. When the two groups were compared after 12months, only the simK1 value was significantly lower in the adult group, and there was no significant difference between the other measurements. There is a slight tendency toward more flattening in the adult group 12months after ACXL treatment, but this is not statistically significant.

Femtosecond laser-induced photochemical synthesis of gold nanoparticles in nitrate solution

Femtosecond laser pulses are capable of ionizing water molecules through multiphoton absorption. The generated hydrated electron and hydrogen peroxide are responsible for the nucleation and growth of nanoparticles during a photochemical synthesis. The photochemical reduction kinetics follow an autocatalytic rate law, which is determined by nucleation rate k1 and growth rate k2. In this work, we investigated the effect of adding nitrate as electron scavenger on the laser-based photochemical synthesis of gold nanoparticle. The experiment results showed enhancements of both k1 and k2 with increasing nitrate concentration, indicating the formation of a large number of nuclei followed by fast growth process. TEM images and size distribution analysis confirmed the improved growth of gold nanoparticles. In the absence of scavenger, the gold nanoparticles produced were dominated by small particles with sizes <7 nm. Adding small amount of nitrate increased the mass fraction of larger particles (∼7–15 nm), thus tuning the average size of gold nanoparticles from 6.52 nm to 7.49 nm. Exceedingly high concentration of nitrate caused the formation of even larger particles, which connected to each other. While salt effects might interfere with both nucleation and growth process, generation of reducing species from electron scavenging reaction significantly contributed to the counterintuitive increase of nucleation rate. This study demonstrated the potential use of nitrate as a modifying agent for morphological control of gold nanoparticles.

Determination of Stability Constant of The Complexes of Metal Ion Fe(III), Mn(II) And Cr(III) With Some Substituted 2-Oxo-2H-Chromene-3-Carbohydrazide Derivatives at 0.1 M Ionic Strength at 42oC

Proton ligand and metal ligand stability constant are measured for Fe(III) and 1, 2-dihydroxy benzene and 1, 5-disulphonic acid complexes . Determination of stability constant of substituted of pyrazoles with rare earth metals form complexes are reported . Effect of temperature on formation constants of 2 acetylpyridine(N benzoyl)glycine hydrazone with lanthanide(III) ions at different ionic strengths are reported. Irving and Rossotti, Herson and Gilbert , Wilkins and Lewis and Rossotti and Rossotti have determined stability constant by Bjerrum-Calvin titration technique . Kabadi , Jahagirdar and Narwade have determined pK values of salicylaldehyde, salicylic acid and sulphonic acid respectively by similar procedure. The metal ligand stability constant of some β-diketones are reported . Stability constants have investigated for some substituted pyrazolines, isoxalline and diketone . The method most frequently applied for study of complex equilibria is pH-metric titration technique . Stepwise formation of mononuclear binary complexes is described by set of equilibrium constants. For pH-metric measurements an electrode must be selected. According to Bjerrum, Martell and Calvin , the formation of complex MLN is stepwise process and one has to deal with a series of equilibria of the type: Irving and Rossotti, Herson and Gilbert , Wilkins and Lewis and Rossotti and Rossotti have determined stability constant by Calvin-Bjerrum titration technique . The value of nA,n, pK, log K1 and log K2 are evaluated by Irving and Rossotti's equation. The stability constant and thermodynamic parameters of complexes containing lighter lanthanides , copper(II) , calcium and magnesium are reported. It is also important in environmental studies , medicinal and industrial chemistry . Effects of transition metal on stability constant of complexes have studied by pH metric method . Bendi , Janrao and Ramteke have studied stability constant of ligands with lanthanide metals complexes.The present work involves pH metric study of substituted 2-oxo-2H-chromene-3-carbohydrazide derivatives with metal ions Fe(III), Mn(II), Cr(III) and Ti(III) at temperature42oC. The Bjerrum-Calvin titration technique as modified by Irving and Rossotti has been employed in the present study. The following three sets of titrations are carried out in sequence.

Exchange Structures Between English Lecturer and Health Information Management Students in English Class at Deli Husada Deli Tua Health Institute

The study reasons were to know what exchanges structures used between English Lecturer and Health Information Management (HIM) students and to obtain development of English learning strategies for health students. This research is conducted by descriptive qualitative. The data were clauses produced by English lecturer and HIM students. The data is analyzed based on Martin theory. In conversation, lecturer tends to has initiative to start it, meanwhile, the students tend to give respond by doing activity (evade) which are instructed by the lecturer. It is found 13 types corresponding moves of information, goods and services exchanges. The dominant exchanges structure were k2^k1 and a1^a2f^a1f. It is found different case, when lecturer gave the information to student that is marked by k1, it is followed by k1 or signed by k2^k1(k2)^k1(k2)^k1. There were two conversational systems namely congruent and metaphorical coding. In conversational structures, as the realizations of conversational systems, it is found some marked structures. Students didn’t answer the question, because undeniable that health students have difficult ability for making dialogue in English therefore lecturer keeps the conversation going by undergone initiative actions such as giving information, asking question or giving instruction but s/he seems to repeat information