scholarly journals RANCANG BANGUN MESIN PENGOLAH GANYONG MULTI FINGSI [Design of Multifunctional Canna Machine]

2017 ◽  
Vol 5 (2) ◽  
pp. 462-471
Author(s):  
Asep Yusuf ◽  
Wahyu Kristian Sugandi ◽  
Zaida ◽  
Ch.F. Godang Tua
Keyword(s):  
Agricultural Land ◽  
Raw Materials ◽  
Test Results ◽  
Human Beings ◽  
Processing Machine ◽  
Engine Design ◽  
Drive Motor ◽  
System Output ◽  
Main Components

Food is a basic requirement for human beings. As the population increases, food demand will continue to increase. Food problems in Indonesia are inseparable from rice and flour, in addition to other foodstuffs such as cassava, corn, and sago (Colas, 1994). Efforts to increase rice production are not easy, since there is a massive diversion of agricultural land functions into residential and industrial areas. Indonesia has the potential of tubers as a source of carbohydrates as well as raw materials of local flour. One of the sources of local starch that can be used as flour is canna (Canna edulis Ker). The obstacles faced by smallholders/ small and medium industries (SMEs) who use canna flour that is in the post-harvest process to produce canna flour. Making starch/ canna flour generally still done traditionally, thus affecting the productivity and quality of flour produced. This study aims to design a multi-function canna processing machine to produce canna flour as food. The research method used is the engineering method, which is the activity of designing the build canna processing machine. Canna machine has been successfully made with two main functions namely: the solvent and slicer. The main components of the machine consist of: frame, solvent unit, slicer unit, transmission system, output outlet, wheel, and drive motor. Dimensions of the machine that is 90 cm long, 85 cm wide and 100 cm high. While the frame dimension is 80 cm long, 70 cm wide and 65 cm high. Functional test results show that all components work properly.   Keywords: canna, canna machine, multifunctional, engine design   ABSTRAK   Pangan merupakan kebutuhan pokok bagi manusia. Seiring dengan meningkatnya jumlah penduduk, maka kebutuhan pangan akan terus meningkat. Masalah pangan di Indonesia tidak terlepas dari beras dan terigu, disamping bahan pangan lainnya seperti ubi kayu, jagung, dan sagu (Colas, 1994). Upaya untuk meningkatkan produksi beras bukan hal mudah, karena banyak terjadi pengalihan fungsi lahan pertanian secara massal menjadi area pemukiman dan industri. Indonesia  memiliki  potensi  umbi-umbian sebagai sumber karbohidrat sekaligus bahan baku tepung lokal. Salah satu tanaman sumber pati lokal yang dapat dijadikan tepung adalah ganyong (Canna edulis Ker). Kendala yang dihadapi oleh petani atau Industri Kecil Menengah (IKM) yang memanfaatkan tepung ganyong adalah pada proses pasca panen untuk menghasilkan tepung ganyong. Pembuatan pati atau tepung ganyong umumnya masih dikerjakan secara tradisional, sehingga mempengaruhi produktivitas serta kualitas tepung yang dihasilkan. Penelitian ini bertujuan untuk merancang bangun mesin pengolah ganyong multi fungsi sehingga dihasilkan tepung ganyong sebagai bahan pangan. Metode penelitian yang digunakan adalah metode rekayasa, yaitu kegiatan merancang bangun mesin pengolah ganyong. Mesin ganyong telah berhasil dibuat dengan dua fungsi utama, yaitu: pemarut dan pengiris. Komponen utama mesin terdiri dari: rangka, unit pemarut, unit pengiris, sistem transmisi, saluran pengeluaran hasil, roda, dan motor penggerak. Dimensi mesin yaitu panjang 90 cm, lebar 85 cm dan tinggi 100 cm. Sedangkan dimensi rangka, yaitu panjang 80 cm, lebar 70 cm dan tinggi 65 cm. Hasil uji fungsional menunjukkan bahwa semua komponen berfungsi dengan baik.   Kata kunci: ganyong, mesin ganyong, multi fungsi, rancang bangun mesin

scholarly journals Prospects Of Using Walnut In Technologies Of Drinks

2015 ◽  
Vol 19 (2) ◽  
pp. 39-50
Author(s):  
Inna Tiurikova ◽  
Mykhailo Peresichnyi
Keyword(s):  
Raw Materials ◽  
Chemical Properties ◽  
The Body ◽  
Maturity Stage ◽  
Human Beings ◽  
Fruit And Vegetable ◽  
Biological Value ◽  
Vegetable Raw Materials ◽  
Main Components ◽  
Physical And Chemical

Abstract The results of studies in the field of beverage functionality using walnut are presented. The main components such as celery, Jerusalem artichokes, carrots, pumpkin and rhubarb, as a dietary supplement - extracts from walnut of milk-maturity stage are offered for creating blends. The basic physical and chemical properties of fruit and vegetable raw materials and semi-finished products created on the base of them have been studied, and their nutritional and biological value has been proved. Rational technologies of fruit and vegetable blends with nut additives have been identified. Their biological value has been confirmed. Drinks are recommended for use in the daily diet of human beings to satisfy thirst and enrich the body by biologically valuable components.

Evaluation and Application of Recipe for Binding Materials in Self-Compacting Concrete

2014 ◽  
Vol 629-630 ◽  
pp. 405-416
Author(s):  
Wei Chung Yeih ◽  
Jiang Jhy Chang ◽  
Mao Chieh Chi ◽  
Cheng Chin Chang ◽  
Ran Huang
Keyword(s):  
Raw Materials ◽  
Setting Time ◽  
Cementitious Materials ◽  
Heat Of Hydration ◽  
Test Results ◽  
New Era ◽  
Materials Research ◽  
Hardened Properties ◽  
The Stability

Concrete consists of many kinds of raw materials, the safety and quality of construction are greatly influenced by the stability of concrete. Thus, how to improve the performance of concrete and construction method, i.e. avoid the bleeding, segregation and honeycomb, etc, becomes a very important issue and imminent mission. This study discusses the different mixing designs of SCC with the amounts of cementitious materials ( OPC, GGBFS, and FA) ranged from 400 - 500 kg/m3. Meanwhile, the fresh and hardened properties of SCC, such as the slump flow, setting time, heat of hydration, and compressive strength were also determined. Test results indicate SCC binding materials can be classified by its compacting ratio. For instance, to pass the boxing test of R1/R2 within and without hindrance, the minimum binding materials should be 500kg/m3, 450kg/m3 and 400kg/m3. The optimum binding materials research shows if use cement, GGBFS and FA at the same time , it can increase the initial and final setting time and decrease the heat of hydration. The SCC binding materials’ concept will meet the requirement of " Safety, Durability, Workability and Ecology " for the new era. Thus, the amount of cement was at least 250kg/m3 or more for SCC mix design and the adding of GGBFS and FA was recommended to maintain 20 - 40 % of all cementitious materials based on the test results.

scholarly journals PROSES PEMBUATAN DAN PENGUJIAN BENDA UJI KERAMIK UNTUK BAHAN BAKU ISOLATOR LISTRIK KERAMIK PORSELEN (MANUFACTURING AND TESTING PROCESS OF CERAMIC SPECIMENS FOR RAW MATERIALS OF ELECTRICAL ISOLATOR PORCELAIN CERAMIC)

2016 ◽  
Vol 10 (3) ◽  
pp. 173-180
Author(s):  
Wahyu wahyu Garinas
Keyword(s):  
Test Object ◽  
Test Specimen ◽  
Raw Materials ◽  
Separation Process ◽  
Raw Material ◽  
Materials Processing ◽  
Test Results ◽  
Composition Materials ◽  
Ball Clay

Penelitian ini merupakan bagian dari kegiatan mencari bahan baku untuk pembuatan isolator keramik porselen. Bahan baku untuk pembuatan benda uji keramik sebagian besar menggunakan bahan baku lokal.Proses pengolahan bahan baku pada penelitian ini  : pembuatan komposisi, pengolahan bahan dan pembuatan benda uji.Metode yang akan dilakukan dalam pengolahan ini  yaitu proses pemisahan dengan cara basah dan kering.Untuk mengetahui kualitas kelistrikan dari bahan baku keramik maka dibuat benda uji dan dilakukan uji tegangan tembus listrik.Hasil uji terhadap benda uji ternyata  semua benda uji masih belum memenuhi standar IEC maupun ASTM. Nilai hasil uji terhadap sampel  sekitar   (7,99 - 9,35) kV/mm dan semua sampel  belum memenuhi  standar yang direkomendasikan oleh PLN (9,85 kV/mm). Hasil uji tersebut menunjukkan bahwa sampel no. 5 dan 6 yang mendekati standar dari PLN. Perlu evaluasi terhadap  komposisi , bahan dan proses pembuatan dari benda uji keramik. Kata Kunci : Bahan mentah keramik (kaolin, felspar, ball clay,kuarsa), pengujian  benda uji, pengujian tegangan tembus, kualitas bahan keramik. Abstract This study is part of the looking for raw materials for the manufacture of ceramic porcelain insulators.The raw material for the manufacture of ceramic test specimens mostly using local raw materials.The processing of the raw material in this study: preparing a composition, materials processing and manufacturing of the test object. The method will be done in this processing is the separation process by means of wet and dry.To know the the quality of the electrical ceramic raw materials then created of the test specimen and test the electrical Puncture Voltage.The test results of the test specimen it turns out all specimens still does not meet PLN (IEC and ASTM) standards.Value test results on samples approximately (7.99 to 9.35) kV / mm and all samples do not meet the standards recommended by PLN.The test results showed that the samples no. 5 and 6 are closer to a standard of PLN.Needs to be evaluation of the composition, materials and manufacturing process of ceramic test specimen. Keywords :  raw material ceramic, specimens test, puncture voltage test, ceramic material quality.

scholarly journals Examination of Technologies and Physical Effects for the Enrichment of Arable Land and Plants Growing on them

2019 ◽  
Vol 8 (3S) ◽  
pp. 537-545
Keyword(s):  
Food Security ◽  
Agricultural Land ◽  
Raw Materials ◽  
Arable Land ◽  
Food Products ◽  
Agricultural Lands ◽  
Foreign Markets ◽  
Innovative Technologies ◽  
Macro Elements

In order to address food security problems in Russia, insufficient attention is paid to the development and implementation of innovative technologies for the enrichment of agricultural lands and plants growing on them. Such technologies make it possible to purposefully bring the necessary micro and macro elements to agricultural plants, while ensuring, in turn, a significant increase in the consumer quality of agricultural products. The article discusses innovative technologies for the enrichment of agricultural land and plants growing on them, the use of which will increase the consumption of agricultural food raw materials from each hectare of arable land, as well as the quality of functional food products produced from it. This will increase the competitiveness of fortified products in the domestic and foreign markets and make an important contribution to improving the food security of the country. The analysis showed that one of the important directions of innovative developments and patents in the field of enrichment of agricultural lands and plants growing on them is the solution to the problem of providing the population of Russia and the world with regulatory requirements for micro and macro elements: iodine, selenium, magnesium, calcium, manganese, zinc, etc., as well as in vitamins by pre-sowing, root, and foliar enrichment of cereal, fruit-bearing and vegetable crops in open and in closed ground. All this, in turn, will help to provide the country's population with high-quality food products derived from enriched agricultural raw materials and increase its competitiveness in the domestic and foreign markets.

Exploring Possibilities of Implementation of Special Rutile Electrodes for Welding Microalloyed Steels

2016 ◽  
Vol 1138 ◽  
pp. 19-24
Author(s):  
Mihailo Mrdak ◽  
Nikola Bajić ◽  
Marko Rakin ◽  
Darko Veljić ◽  
Zoran Karastojković ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Weld Metal ◽  
Microalloyed Steel ◽  
Raw Materials ◽  
Microalloyed Steels ◽  
Test Results ◽  
Medium Thickness ◽  
Cored Wire ◽  
Ni Content

The paper presents test results of a new quality of a special rutile electrode, with a core of flux-cored wire made from local raw materials, based on analyzing mechanical properties and microstructure of the weld metal in MMA welding. The base metal for experimental welding was microalloyed steel marked J55 (thickness 7.0 mm) according to API Spec 5L standards (EN 10113-3. and JUS C.B0 502) which was produced in Smederevo steelworks. For experimental welding a special electrode IHIS E 35 R-2 was used, with a medium thickness rutile coating, a core of flux-cored wire and Ni content of 2.5%. The results of the analyzes indicate that the new quality special rutile electrode with the flux-cored wire core provides good structural and mechanical properties of weld metal in microalloyed steel welded joints.

scholarly journals Analisis Pengendalian Kualitas Bahan Baku Acrylic Resin Pada Produk Spray Paint di PT X

2021 ◽  
Vol 1 (1) ◽  
pp. 31-41
Author(s):  
Nurlita Utami ◽  
Sena Atmaja ◽  
Yogi Priyo Istiyono
Keyword(s):  
Raw Materials ◽  
Film Formation ◽  
Acrylic Resin ◽  
Raw Material ◽  
Test Results ◽  
Literature Study ◽  
Factors Affecting ◽  
Analysis Process ◽  
Poor Adhesion

Thermo Plastic Acrylic resin has an important role in the manufacture of spray paint, namely as a binder or binder. The resin in paint has a function as a film formation, has adhesion to the substrate as well as pigment binders and additives, so that to produce a spray paint with good quality mechanical properties, PT X must be selective in controlling the quality of the raw material for Thermo Plasic Acrylic Resin. The purpose of this study was to determine the problems faced by PT X related to the quality of Thermo Plastic Acrylic Resin raw materials, to identify the most dominant factors affecting the quality of these raw materials and to formulate the most appropriate solutions to be applied in improving the quality of these raw materials. This research uses observation, interview, and literature study methods. Sources of data came from stakeholders and quality control staff of PT X. This study used check sheets, histogram diagrams, u-control maps, and fishbone diagrams to complete the analysis process. From the test results of the Thermoplastic Acrylic Resin raw material, it is known that the factor that causes rejection is due to adhesion, namely 53.57%, gloss 33.33%, and dry touch 13.10%, all three of the total raw materials that are rejected when the raw material is applied in form paint and spray on the film plate. The most dominant cause of reject was poor adhesion, namely 53.57% of the total reject raw materials.

scholarly journals OPTIMASI PARAMETER PROSES PEMBUATAN BIOETANOL SORGUM DAN PENGARUH TERHADAP UNJUK KERJA MOTOR BENSIN

Otopro ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 39
Author(s):  
Teng Sutrisno ◽  
Willyanto Anggono ◽  
Kurniawaan Lay ◽  
Melvin Emil Simanjuntak
Keyword(s):  
Laboratory Test ◽  
Raw Materials ◽  
Test Results ◽  
Alcohol Content ◽  
Fermentation Time ◽  
Renewable Fuel ◽  
Gasoline Engines ◽  
Laboratory Test Results

Bioethanol is a renewable fuel that resembles gasoline, bioethanol is produced from fermentation and distillation processes. One of the raw materials that produce bioethanol is Sorghum. Sorghum was chosen because it is superior to other plants. This study aims to analyze fermentation longtime and enzyme composition for the best composition to produce bioethanol from sorghum, and determine the quality of sorghum bioethanol. This research Sorghum  bioethanol produced with an alcohol content of 94%. The test and analysis variables used were 31 samples. The results of this study are as follows : The best fermentation time is 4 days, the enzyme and yeast variable for the most volume of alcohol is 7% yeast 5% enzyme, the enzyme and yeast variable for the highest alcohol content is 7% yeast 7% enzyme. Laboratory test results when compared with PERTAMINA's standard regulations, especially Pertalite RON 90, Several parameters have rejected the regulations. Therefore sorghum bioethanol is used as an additive for Gasoline. Sorghum bioethanol is made addictive to gasoline RON 90, namely B10 (bioethanol sorghum 10%) and B20 (bioethanol sorghum 20%). It would cause an increase in the performance of gasoline engines.

scholarly journals Interlaboratory comparisons of the results of the work of the chemical­analytical unit of JSC “The URIR named after A. S. Berezhnoy” in 2018

2019 ◽  
Vol 119 ◽  
pp. 127-133
Author(s):  
E. A. Bondarenko ◽  
V. V. Varganov ◽  
N. N. Konchinko
Keyword(s):  
Refractory Plant ◽  
Interlaboratory Comparison ◽  
Refractory Industry ◽  
Raw Materials ◽  
Quality Monitoring ◽  
Interlaboratory Comparisons ◽  
Test Results ◽  
Work Quality ◽  
Activity Areas

One of the activity areas of JSC “The URIR named after A. S. Berezhnoy” is assistance to refractory industry enterprises of Ukraine in ensuring their work in the quality monitoring of products and raw materials. The comparison of work quality of chemical­analytical units of following enterprises: JSC “KDZ”, PJSC “Chasovoyarsk Refractory Plant”, JSC “Velikoanadol Refractory Plant” and JSC “The URIR named after A. S. Berezhnoy” was carried out. The discrepancy between the average results of components determination in the chemical­analytical units of refractory enterprises and in the chemical­analytical laboratory of JSC “The URIR named after A. S. Berezhnoy” does not exceed the value of  in terms of ND. The work quality of chemical­analytical units of central refractory laboratories of all the above mentioned enterprises is satisfactory. Recommendations to improve the accuracy of analysis results are not required. The work on interlaboratory comparison of work results of the chemical­analytical unit of JSC “The URIR named after A. S. Berezhnoy” and IP “SGS Ukraine” was completed. The quality of interlaboratory comparisons carried out between the Testing Centre of IP “SGS Ukraine” and JSC “The URIR named after A. S. Berezhnoy” was found to be satisfactory. The test results were accepted by the NAAU during the next inspection as corresponding to DSTU ISO / IEC 17025:2006.

scholarly journals The Effect of Cocoa Beans Heavy and Trace Elements on Safety and Stability of Confectionery Products

2016 ◽  
Vol 35 (330) ◽  
pp. 19-23 ◽  
Author(s):  
Vineta Vītola ◽  
Inga Ciproviča
Keyword(s):  
Oxidative Stability ◽  
Raw Materials ◽  
Cadmium Concentration ◽  
Human Beings ◽  
Cocoa Beans ◽  
Milk Chocolate ◽  
Confectionery Products ◽  
Zinc Concentrations ◽  
Quality Of Products

Abstract The aim of the study was to evaluate cocoa beans quality produced in Cameroon, Ecuador, Nigeria and Ghana from safety position determining heavy and trace metals concentration and evaluating the oxidative stability of confectionery products prototypes (trials) with analysing cocoa beans. For evaluation of oxidative stability of confectionery products, the main ingredients - butter and cocoa beans kernels were tested making trials as milk chocolate prototype. The composition of confectionery ingredients affects quality of products; therefore it is very important to evaluate quality of raw materials in confectionery industry, as they are purchased practically in all regions of the world. Mercury, arsenic, lead, cadmium concentration was determined in whole cocoa beans as their presence in foods have toxic effect on human beings and their concentration are strictly limited as maximum residue limits for processing. Cocoa shells can be used as additive to confectionery products recipes therefore the object of the study was cocoa beans and cocoa shells. Analyzing cocoa beans quality indices there was established that lead, cadmium, aluminium and zinc concentrations vary in cocoa beans significantly. Differences in lead concentration in cocoa beans from Ghana, Cameroon and Ecuador were significant (p < 0.05) compared with concentration of lead in cocoa beans from Nigeria (p > 0.05). Cadmium concentration in cocoa beans from Cameroon was significantly different comparing with cocoa beans from Nigeria, Ecuador and Ghana (p > 0.05). Differences in aluminium concentration in cocoa beans kernels were significant (p < 0.05) in all analyzed samples. Concentration of zinc was higher in shells of cocoa beans, especially in shells of cocoa beans from Ecuador (p < 0.05). The presence of cocoa products in milk chocolate prototypes inhibited the speed of lipid peroxidation. The different trace and heavy metals concentrations in cocoa beans should be taken into account choosing ingredients and components for confectionary products production particularly those with high content of cocoa (chocolates, sweets, cocoa fillings, cocoa creams and others) with the aim to prevent oxidation process during shelf-life of products.

scholarly journals Variety test results of durum wheat “Sondor” varieties

2020 ◽  
Vol 29 (1) ◽  
pp. 107-113
Author(s):  
Sansargerel Tsagaanshukher ◽  
Myagmarsuren Yadamsuren
Keyword(s):  
Durum Wheat ◽  
Wheat Flour ◽  
Digestive System ◽  
Raw Materials ◽  
Weather Condition ◽  
Vitamin B ◽  
Test Results ◽  
High Quality ◽  
Scientific Organizations

Durum wheat is considered valuable kind of wheat because of its high protein content, carotenoids, and high-quality gluten. In addition, not only the semolina and the porridge are made from durum wheat but also the premium pasta, fine noodles and various biscuits can be made from it. Durum wheat is rich in carbohydrates, proteins, fiber, iron, and vitamin-B, and support weight loss, heart health, and digestive system. Also, durum wheat can be mixed with soft wheat flour and used for increasing the quality of bread. It improves the tastiness of bread and extend the shelf life. In Mongolia, flour manufacturers start milling the wheat with high-gluten first. Therefore, the bad quality wheat is used from mid- February. Due to that we import the high-gluten wheat from abroad. Currently, cultivation in Mongolia where there are no domesticated versions of durum wheat. The price of wheat is being set depending on its seed gluten, which has greatly increased the farmers' interest in growing durum wheat. Flour manufacturers are aiming to produce more products by durum wheat and proposing to cooperate with scientific organizations. In order to create raw materials to replace the imported products and find sort that adaptability of soil and weather condition of Mongolia, to increase the productions’ the Sondor variety of durum wheat is introduced. The variety is early-controlled, with a yield of 2.8 c/ha from the Pletcher variety and, according to economic indicators, can produce up to 252.0 thousand Mongolian tugriks per seed per 1 ha and 168.0 thousand tugriks per hectare. Хатуу буудайн “Сондор” сортын сорт сорилтын дүн  Хатуу буудай нь уургийн агууламж ихтэй каротиноидууд, онцгой чанартай цавуулагтай тул үнэ цэнэтэйд тооцдог. Түүгээр ширхэгтэй гурил (семолина), хүүхдийн будаа хийхээс гадна дээд зэргийн гоймон, нарийн гоймон, төрөл бүрийн жигнэмгийг зөвхөн хатуу буудайгаар хийнэ [1]. Нүүрс ус, уураг, эслэг, төмөр, В төрлийн амин дэмээр баялаг бөгөөд жин хасах, зүрхний эрүүл мэнд, хоол боловсруулалтыг дэмжих зэрэг үйлчилгээтэй [2]. Хатуу буудайг тусгай хэмжээгээр зөөлөн буудайн гурилтай хольж талхны чанарыг сайжруулагч болгон ашиглаж талхны амт чанарыг дээшлүүлж, хадгалах хугацааг уртасгадаг. Монгол орны хувьд гурил үйлдвэрлэгчид цавуулаг ихтэй буудайгаа эхэлж тээрэмдэн 2-р сарын дунд үеэс эхлэн чанар муутай нь үлддэг тул гаднаас цавуулаг ихтэй буудайг импортоор оруулж ирдэг байна. Одоогоор Монгол оронд хатуу буудайн нутагшсан сорт байхгүй тариалалт ч бага хийгдэж байна. Гурилын үйлдвэр болон ТЭДСан /Тариалан эрхлэгчдийг дэмжих сан/-д авах буудайн үнийг түүний үрийн цавуулгаас хамааруулан тогтоож байгаа нь тариаланчид хатуу буудай тариалах сонирхлыг ихээхэн нэмэгдүүлж байна. Гурил үйлдвэрлэгчид хатуу буудайгаар бүтээгдэхүүн хийх эрэл хайгуул нэмэгдэн Эрдэм шинжилгээний байгууллагуудад хамтран ажиллах санал ихээр тавьж байна. Монгол орны хөрс, цаг уурын нөхцөлд зохицсон хатуу буудайн эрт болцтой, арвин ургацтай, чанартай сортыг үйлдвэрлэлд нэвтрүүлэхээр бүтээгдэхүүний гарц, чанарыг сайжруулах, зарим импортын бүтээгдэхүүнийг орлох түүхий эд бий болгох зорилгоор хатуу буудайн селекцийн ажлын үр дүнд Сондор сортыг нутагшуулаад байна. Уг сорт нь эрт болцтой, хяналт Pletcher сортоос 2.8 ц/га нэмүү ургацтай, эдийн засгийн үзүүлэлтээр хяналт сорттой харьцуулахад 1 га-аас үрэнд борлуулахад 252.0 мян.төгрөг, таваарт борлуулахад 168.0 мянган төгрөгийн нэмүү бүтээгдэхүүн үйлдвэрлэх боломжтой.  Түлхүүр үг: уураг, цавуулаг, чанар, гурил, талх

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