Changes In Stone Research Articles

Stone deterioratins in Mardin Madrasas: The case of Şehidiye and Kasımiye Madrasas

Stone is a widely used building material in cultural heritage buildings due to its petrographic properties. However, changes occur on the stone surfaces of the buildings due to exposure to environmental and climatic factors. Therefore, it is of great importance to detect these changes and take measures for the long-term preservation of these structures. The aim of this study is to identify and classify the stone changes observed in Şehidiye and Kasımiye madrasahs in Mardin. In addition, the similarities and differences of the changes and the causes of the changes will be determined. The study includes the identification and classification of stone alterations based on a general literature review, visual inspection of the alterations and mapping methodology. Observed changes were identified through visual inspection, categorized as physical, chemical, biological or anthropogenic, and photographed for documentation. A mapping method was used to determine the extent of change, which involved calculating the ratio of observed changes to total façade area. The changes on each façade were then analyzed to determine their causes. The impact of the same changes on the various structures and their proportions in relation to the façade were compared.

Geomechanical research into surface coal mining in terms of geotechnical safety substantiation

Purpose. The purpose of the present study is to determine the geomechanical parameters for calculating the stability of side slopes by partial and general angle in the working front to ensure the completeness of coal mining in accordance with geotechnical rules and standards based on the regulations (EC-7) of the Kosovo Energy Corporation, which is the state corporation, producing not only electricity in the Republic of Kosovo. Methods. In the course of the present study, 60 additional drillings were carried out to a depth of 150 m up to green clay contact to determine the coal thickness. It was realized using a Type EK-650 drilling machine and a drilling diameter of 145/101 mm. To determine the angle φ and cohesion C, two methods were used, such as the Direct test and the Triaxial test. To obtain the most accurate results, a mathematical model was used to derive geomechanical parameters for calculating the slope geometry for the design geometry, where coal is mined to achieve a safety factor according to geotechnical standards. Findings. The regularities of changes in surface gloss of facing stone after its chemical treatment have been specified. It has been proved that all chemical impregnations increases stone gloss; the lower the initial indices of the natural stone surface gloss are, the greater stone changes are observed. In turn, that is caused by the fact that each type of natural stone has its own gloss limit. The regularities of lightness changes and surface saturation of natural facing stone after chemical treatment have been defined. They indicate that all agents reduce lightness and increase saturation of the natural stone surface (except Impregnation agent 3). According to the identified regularities, it is possible to control quality indices of the natural stone surface with simultaneous provision of uniform colour shade of a stone-faced building. The main problem arising during the study of surfaces of natural stone samples by means of infrared spectroscopy was inhomogeneity of its mineral-chemical composition over the sample area. As a result, various spectra have been obtained that are difficult to identify without the prepared reference samples. Complete infrared spectra of the natural stone surfaces of Pokostivskyi granodiorite and Bukivskyi gabbro. Both Pokostivskyi granodiorite and Bukivskyi gabbro have different infrared spectra within the analyzed range of wavelengths that can be explained by the difference in mineralogical composition of both natural stone types. Originality. A large number of physical-mechanical parameters were analyzed, including a mathematical model, with which the slope geometry was calculated using the design profiles and 9 methods. This has given satisfactory results based on Eurocode EC-7 which can be implemented in the field. Practical implications. To analyze the numerical and analytical methods for the design slope geometry, geotechnical Eurocodes were used according to two standards: Eurocode EC7-1 for geotechnical designs and Eurocode EC7-2 for field verification. They were tested on two factors: Category of terrain and Category of objects (excavator), to remove the coal cover using technology in compliance with the conditions in the field, such as the presence of surface water, underground waters and tectonics. This whole analysis is time consuming, so a safety factor has been determined based on the numerical analysis data.

Quality index control for building products made of natural facing stone

Purpose is to assess the influence of technological and natural factors on the decorative properties of natural facing stone to identify the regularities of changes in lightness and saturation of its surface. Methods. To assess the effect of technological and natural factors on the decorative properties of natural facing stone, methods of digital processing of images and infrared spectroscopy have been applied. The methods make it possible to obtain the data on the influence of mineralogical and chemical composition on the decorative properties of natural stone and characterize the physicochemical processes that occur during the natural stone processing by different methods. Findings. The regularities of changes in surface gloss of facing stone after its chemical treatment have been specified. It has been proved that all chemical impregnations increases stone gloss; the lower the initial indices of the natural stone surface gloss are, the greater stone changes are observed. In turn, that is caused by the fact that each type of natural stone has its own gloss limit. The regularities of lightness changes and surface saturation of natural facing stone after chemical treatment have been defined. They indicate that all agents reduce lightness and increase saturation of the natural stone surface (except Impregnation agent 3). According to the identified regularities, it is possible to control quality indices of the natural stone surface with simultaneous provision of uniform colour shade of a stone-faced building. The main problem arising during the study of surfaces of natural stone samples by means of infrared spectroscopy was inhomogeneity of its mineral-chemical composition over the sample area. As a result, various spectra have been obtained that are difficult to identify without the prepared reference samples. Complete infrared spectra of the natural stone surfaces of Pokostivskyi granodiorite and Bukivskyi gabbro. Both Pokostivskyi granodiorite and Bukivskyi gabbro have different infrared spectra within the analyzed range of wavelengths that can be explained by the difference in mineralogical composition of both natural stone types. Originality is in identifying the regularities of changes in lightness and saturation of the natural facing stone surface after its chemical treatment. Practical implications. The determined regularities of changes in lightness and saturation of the natural facing stone surface can help control the quality indices of the natural stone surface with the simultaneous provision of uniform colour shade of a stone-faced building.

ENERGY-EFFICIENT LIGHTWEIGHT CONCRETE FOR GREEN CONSTRUCTION

This article presents the results of studies of energy-efficient wood concrete using ash Astana-Energy CHPP-2. It was found that the use of ash improves the adhesion of rice husks with cement and has a positive effect on the workability of the wood concrete mixture. The optimal ash content of lightweight concrete is 10%, since a further increase in its amount reduces strength by 30-41%. As a result the composition of energy-efficient wood concrete on rice husk for energy-efficient construction was obtained. It was also found that when rice husks are treated with chemical additives, the strength of its adhesion to cement stone changes, and when soaked in water at 40°C with the addition of liquid glass and urea, it increases by 40%.

MP26-03 24-HOUR URINE TEST CONTRIBUTES TO THE DECREASED RISK OF RECURRENT STONE EVENTS

You have accessJournal of UrologyCME1 May 2022MP26-03 24-HOUR URINE TEST CONTRIBUTES TO THE DECREASED RISK OF RECURRENT STONE EVENTS Rei Unno, Xavier Cortez, Leslie Charondo, Kevin Chang, Nizar Hakam, Carter Chan, Heiko Yang, Gregory Hosier, Fadl Hamouche, David Bayne, Marshall Stoller, and Thomas Chi Rei UnnoRei Unno More articles by this author , Xavier CortezXavier Cortez More articles by this author , Leslie CharondoLeslie Charondo More articles by this author , Kevin ChangKevin Chang More articles by this author , Nizar HakamNizar Hakam More articles by this author , Carter ChanCarter Chan More articles by this author , Heiko YangHeiko Yang More articles by this author , Gregory HosierGregory Hosier More articles by this author , Fadl HamoucheFadl Hamouche More articles by this author , David BayneDavid Bayne More articles by this author , Marshall StollerMarshall Stoller More articles by this author , and Thomas ChiThomas Chi More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002569.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Although the AUA guideline recommends metabolic testing in first-time stone formers with high-risks and recurrent stone formers, this is not often followed in real world practice. This study aimed to understand the characteristics of patients undergoing 24-hour (24h) urine testing, as well as the direct impact of the metabolic testing on the changes in stone burden/number and recurrent stone events during follow-up. METHODS: This was an analysis of prospectively collected data from the Registry for Stones of the Kidney and Ureter (ReSKU) from a single institution between October 2015 and May 2021. We compared demographics and clinical information between individuals with a 24h urine test and those without a test. We also collected data on changes in stone burden/number and stone events during the period from the initial clinic visit to the next clinic visit. Univariate and multivariate logistic regression analyses were performed to identify the factors associated with the clinical severity of urolithiasis. RESULTS: Of 1921 patients analyzed, 564 patients (29.3%) underwent a 24h urine test. Patients who agreed to perform a 24h urine test were more often highly educated, non-smokers, and had hyperlipidemia (HL), a past stone history and a positive family history of urolithiasis. They also were more likely to present with a higher stone burden and bilateral stones. Over a median follow-up period of 5 months, those with a 24h urine testing were less likely to have an increase their stone burden and number on imaging and experience stone events than those without a 24h urine test. On multivariate analysis, undergoing a 24h urine test remained a statistically significant factor decreasing the risks of an increase in stone burden and number and recurrent stone events (OR 0.57 p<0.001, OR 0.68 p=0.035, respectively) (Table1). CONCLUSIONS: Consistent with the AUA guidelines, when metabolic testing was performed in patients with high-risk for stone recurrence these patients experienced fewer recurrent stone events. These data support that metabolic testing should be performed more frequently in patients with first time kidney stones. Source of Funding: none © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e439 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Rei Unno More articles by this author Xavier Cortez More articles by this author Leslie Charondo More articles by this author Kevin Chang More articles by this author Nizar Hakam More articles by this author Carter Chan More articles by this author Heiko Yang More articles by this author Gregory Hosier More articles by this author Fadl Hamouche More articles by this author David Bayne More articles by this author Marshall Stoller More articles by this author Thomas Chi More articles by this author Expand All Advertisement PDF DownloadLoading ...

Influence of superplasticizer additive on the strength of cement stone during wetting–drying cycles

This article discusses the issues of durability of reinforced concrete structures exposed to drying–wetting cycles. Transport structures are under the constant wetting and drying cycles, but rarely completely dry out, as the saturation process occurs faster drying. Such cycles cause moisture migration inside the concrete, which leads to leaching of calcium hydroxide Ca (OH)2. The structure of the cement stone changes over time, and the dissolution of cement hydration products additionally leads to a strength decrease. Were tested the influence of the alternation of cycles of water saturation and drying of concrete on tensile strength, as the most sensitive characteristic to changes in the structure of the material. Since at present most concretes are manufactured using plasticizing additives, the tests were carried out with different content. The studies show that regardless of the amount of plasticizing additive in the samples, the flexural strength decreases. The compressive strength gradually increased, which is probably due to the ongoing process of hydration of the cement grains.

Genetic ancestry changes in Stone to Bronze Age transition in the East European plain.

The transition from Stone to Bronze Age in Central and Western Europe was a period of major population movements originating from the Ponto-Caspian Steppe. Here, we report new genome-wide sequence data from 30 individuals north of this area, from the understudied western part of present-day Russia, including 3 Stone Age hunter-gatherers (10,800 to 4250 cal BCE) and 26 Bronze Age farmers from the Corded Ware complex Fatyanovo Culture (2900 to 2050 cal BCE). We show that Eastern hunter-gatherer ancestry was present in northwestern Russia already from around 10,000 BCE. Furthermore, we see a change in ancestry with the arrival of farming-Fatyanovo Culture individuals were genetically similar to other Corded Ware cultures, carrying a mixture of Steppe and European early farmer ancestry. Thus, they likely originate from a fast migration toward the northeast from somewhere near modern-day Ukraine-the closest area where these ancestries coexisted from around 3000 BCE.

Composition analysis and related risk factors of recurrent upper urinary tract calculi

Objective To analyze the composition and risk factors of recurrent upper urinary tract calculi. Methods From September 2015 to December 2017, 120 cases of recurrent upper urinary calculi in our hospital were selected.The clinical data of all the subjects were analyzed retrospectively.The changes of stone components before and after the recurrence of calculi were analyzed, and the risk factors for the changes of recurrent stones were evaluated. Results Recurrent upper urinary calculi in 120 cases, calcium oxalate stone in 50 cases, calcium phosphate stone in 24 cases, infectious stone in 20 cases, uric acid stone in 10 cases, and cystine stone in 16 cases were found. Eighty patients had unchanged stone composition and 40 patients had changes in stone composition.Patients with recurrent upper urinary tract stones were closely related to stone type, recurrence time and other factors.The difference was statistically significant(P<0.05). Conclusions The main changes of calculus in recurrent urinary calculi are the conversion of calcium oxalate stones and infectious stones.The main risk factors for the change of stone composition are the time of recurrence.Patients with recurrent stone for more than 5 years or less than 1 year need to be rechecked regularly. Key words: Urinary Calculi; Risk Factors

Assessment Techniques for Studying the Effects of Fire on Stone Materials: A Literature Review

ABSTRACT Fire is one of the most severe threats to stone applied in civil engineering and architecture. In most cases, its effects are irreversible and have long-lasting repercussions. In addition to aesthetic alterations, fire can also induce important mineral-chemical, physical, and mechanical changes in stone. Research concerning the effects of fire on stone materials in recent decades has been providing valuable knowledge to inform present and future conservation and restoration actions. In this literature review, the properties and techniques used for studying the effects of fire on stone materials are appraised, summarized, and compiled. A comprehensive and practical overview of those effects is also given. Open porosity and P-wave ultrasonic velocity are the physical and mechanical properties that have been studied most. Other frequently researched areas include chemical-mineralogical changes, color, density, water absorption, uniaxial compressive strength, and modulus of elasticity are also very frequently investigated.

Isolated Tracheobronchial Hyperkeratosis

SESSION TITLE: Bronchology SESSION TYPE: Case Report Slide PRESENTED ON: Sunday, April 17, 2016 at 02:15 PM - 03:45 PM INTRODUCTION: Airway hyperkeratosis is uncommon and affects upper airway, such as the laryngeal area in most cases. Tracheobronchial involvement is very rarely reported, and here we report a case of isolated tracheobronchial hyperkeratosis. CASE PRESENTATION: An otherwise healthy 32-year-old man presented with recurrent cough, sputum production and intermittent low-grade fever over three years. He had been treated as bronchitis with antibiotics, and the above symptoms could be relieved temporarily. He had a 5 pack year history of smoking and had quit 3 years ago. He worked in an open-air steel market with heavy ground dust pollution. Physical examination revealed no significant abnormalities. His tuberculin skin test and T-spot. TB blood test were both negative. Pseudomonas aeruginosa were seen in sputum cultures. Spirometry showed mild airflow obstruction. Chest CT scan showed no significant abnormalities. Bronchoscopy revealed diffuse white nodules like paving stone changes in the tracheobronchial mucosa with no laryngeal area involvement (Panel A, B and C). The results of tissue stains and cultures for acid-fast bacilli and fungal organisms were negative. Multiple tracheobronchial mucosa biopsy showed squamous cell metaplasia and hyperkeratosis, with no dysplasia or malignancy (Panel D). DISCUSSION: Lower airway hyperkeratosis is very rare and isolated tracheobronchial involvement has not been documented before. The cause of airway hyperkeratosis is not clear and maybe related with chronic inflammatory stimulus, air pollution, inhalation of poisonous gases, occupational dust exposure or trace element deficiency. The tracheobronchial hyperkeratosis may occur as a result of smoking and chronic dust exposure in this patient who maybe genetically predisposed to such lesions. The relationship between chronic airway infection and hyperkeratosis has not been determined. Does chronic airway infection serve as an incentive for hyperkeratosis? Or loss of normal clean function of airway secondary to hyperkeratosis, induced recurrent infection. Tracheobronchial hyperkeratosis should be differentially diagnosed from bronchial tuberculosis and fungus infection. There is no specific treatment for airway hyperkeratosis yet. The primary concern for the management of airway hyperkeratosis is the potential for malignant conversion. The risk is increased by the presence of dysplasia, since increasing severity of dysplasia appears to increase the risk of malignant conversion. Hence close follow-up with surveillance bronchoscopy is ongoing for this subject. CONCLUSIONS: Lower airway hyperkeratosis has no specific clinical characteristics. Broncoscopy with multiple-section histopathological analysis is necessary for accurate diagnosis. Close follow-up is mandatory due to its potential for malignant conversion. Reference #1: Isenberg et al. Institutional and Comprehensive Review of Laryngeal Leukoplakia. Annals of Ototogy, Rhinology & laryngology. 117(l);74-79. DISCLOSURE: The following authors have nothing to disclose: Xiaolei Zhang No Product/Research Disclosure Information

Dimensional changes in stone casts resulting from long-term immersion of addition-type silicone rubber impressions in disinfectant solutions

There is a concern that long-term immersion of impressions in disinfectant solutions may cause changes in the dimensions of the resulting stone casts. This study investigated the dimensional changes in stone casts resulting from immersion of five brands of addition-type silicone rubber impressions in disinfectant solutions for 30 min and 24 h. Impressions of a master cast designed to simulate an abutment tooth were immersed in 2% glutaraldehyde and 0.55% ortho-phthalaldehyde. The diameter of the stone cast was measured using a laser scan micrometer. For four brands of impression materials, 30-min immersion in disinfectant solutions produced no dimensional changes in the stone casts. For four brands of impression materials, 24-h immersion caused a significant decrease in the stone cast dimensions.

Functional experiment design for the analysis of colour changes in granite using new [formula omitted] functional colour coordinates

We propose a functional data approach to evaluating colour changes in stone that is based on applying a functional experiment design to the tristimulus curves resulting from the product of the power spectral distribution of the source, the stone reflectance curve and the matching colour functions of the standard observer.The proposed method was applied to an analysis of colour changes in granite after the application of different desalination treatments. The results were compared with those obtained by the classical analysis of variance applied to the colorimetric coordinates L∗a∗b∗.The granite RGB and XYZ colour coordinate systems were obtained by integrating the respective tristimulus curves. The L∗a∗b∗ coordinates, however, were obtained directly by transforming the XYZ coordinates, as no corresponding tristimulus functions have been proposed to date. With a view to comparing the results for these functional and scalar methods for a uniform colour measurement system, these functions, whose integral coincides with the L∗a∗b∗ values, have been deduced and proposed for the first time.The results obtained demonstrate the usefulness of the additional information supplied by the functional approach. However, this information does not replace that produced by the scalar approach for the scalar coordinates, and so it is recommended to use both approaches. The new tristimulus functions associated with the L∗a∗b∗ coordinates are perfectly interpretable in a way analogous to the coordinates themselves, i.e., as the degree of luminosity (L∗), the green–red relative position (a∗) and the blue–yellow relative position (b∗), except that they are interpreted for each infinitesimal wavelength interval.A brief introduction to the colour measurement problem and to functional statistical techniques is provided for readers coming from different disciplines.

Biosorption kinetics of Cd (II), Cr (III) and Pb (II) in aqueous solutions by olive stone

A by-product from olive oil production, olive stone, was investigated for the removal of Cd (II), Cr (III) and Pb (II) from aqueous solutions. The kinetics of biosorption are studied, analyzing the effect of the initial concentration of metal and temperature. Pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models have been used to represent the kinetics of the process and obtain the main kinetic parameters. The results show that the pseudo-second order model is the one that best describes the biosorption of the three metal ions for all the range of experimental conditions investigated. For the three metal ions, the maximum biosoption capacity and the initial biosorption rate increase when the initial metal concentration rises. However, the kinetic constant decreases when the initial metal concentration increases. The temperature effect on biosorption capacity for Cd (II) and Cr (III) is less significant; however, for Pb (II) the effect of temperature is more important, especially when temperature rises from 25 to 40ºC. The biosorption capacity at mmol/g of olive stone changes in the following order: Cr>Cd>Pb. Thus, for an initial concentration of 220 mg/ℓ, a maximum sorption capacity of 0.079 mmol/g for Cr (III), 0.065 mmol/g for Cd (II) and 0.028 mmol/g for Pb (II) has been obtained.

An effective method for controlling a blast furnace

In conclusion, we have developed a method for blast furnace control utilizing hot metal temperature as the guide, blast moisture as the control variable and stone changes to compensate for variations in sinter basicity. Use of these principles has been successfully demonstrated on operating blast furnaces. Further improvements will occur as the system is utilized but it can be used effectively now with only slight modification on any blast furnace.

A descriptive Catalogue of some of the Species of Ammonites from the Inferior Oolite of Dorset

Before commencing a descriptive catalogue of these Ammonites, it may be as well to give some idea of the various beds from which they come. This has been done before; but, various mistakes having crept in and new researches having given us fresh information, I deem it worth while to reintroduce the subject. The beds under consideration begin with the “Sands” or “Passage-beds,” also called Midford Sands. They are from about 100 to 150 feet, perhaps more, in thickness, with interpolated layers of comminuted shells about a foot or so thick, occurring at intervals of from 4 to 10 feet. These layers contain a large conglomeration of broken shells, so that good specimens are scarce. I have obtained from them a Rhynchonella which is probably R.cynocephala (Richard.), besides Harpoceras Moorei (Lycett), and several species of Trigonia (clavellated and costate), Lima, Astarte , &amp;c.; and I am led to suppose that these sands are probably equivalent to the lower part of the Cynocephala stage of Lycett, in the Cotteswold Hills. Above these sands comes the stone of the Inferior Oolite. This stone changes at certain levels, both in composition, colour, and hardness. The Ammonites do not occur all in one bed, but this Inferior Oolite stone can be very well divided into four zones, which are extremely well marked, but vary very greatly in thickness at different localities; and it is probably this variation in thickness, and sometimes almost complete absence of a zone, that has led to very much confusion. At