Medžiagų bandymai pirkti naudotą (470)

Būklė: naudotas, Inductive Conductivity Transmitter Hodob Uhtgjpfx Ab Sefd -Type: 2AMLid-184 -Sensor immersion depth: 1115 mm -Total length: 1337 mm -Weight: 3 kg

Būklė: naudotas, Data acquisition device, test instrument, telemetry system -Axon: J1-CS10 torque telemeter Hfodpfx Abjfg E Hae Sjd -Dimensions: 205/60/H110 mm -Weight: 0.8 kg

Būklė: geras (naudotas), Clamping jaws for round specimens - Manufacturer: VAS, clamping jaws for round specimens, 4 pieces - Type: 15-30 mm Hjdpfemiqm Sjx Ab Sjfd - Dimensions: see technical drawing in photo - Case dimensions: 270/230/H80 mm - Weight: 6.2 kg

Būklė: naudotas, Inductive Conductivity Transmitter, Conductivity Transmitter, Conductivity Measurement Hedpfx Aboldk I De Sefd -Manufacturer: E+H Endress + Hauser, Conductivity Transmitter -Type: conducta XR 2 -100434-0100 -Measuring Range: 0 to 100% Voltage: 220 V 50/60 Hz Dimensions: 180/95/H95 mm Weight: 0.8 kg

Būklė: naudotas, Data acquisition device, testing instrument, telemetry system, CAN-Bus monitoring -Gemac: CANobserver .: 22550-00 -Quantity: 1 unit Hedpfx Asfg E E Nob Sefd -Dimensions: 115/50/H125 mm -Weight: 0.5 kg

Būklė: naudotas, Data acquisition device, testing device, telemetry system -Telemetry Division: Microdac B1A Hfedpsfg E E Uefx Ab Ssd -Frequency: 10.7 MHz -Price: per unit -Quantity: 2 units -Dimensions: 220/105/H85 mm -Weight: 1.0 kg/unit

Būklė: geras (naudotas), Baltographe, Baltograph -Dimensions: 715/270/H410 mm Hedpfsd Sacpsx Ab Sefd -Weight: 78.5 kg

Būklė: naudotas, Inductive Conductivity Transmitter, Conductivity Transducer, Conductivity Measurement Hfjdeldk Ikspfx Ab Sod -Manufacturer: E+H Endress + Hauser, Conductivity Transmitter -Type: Conducta XR 2 -Measuring range: 0 to 200 mS -Voltage: 220 V 50/60 Hz -Dimensions: 180/95/H95 mm -Weight: 0.8 kg

Būklė: beveik kaip naujas (naudotas), BINDER Refrigerated Incubator KB 240 (E5.1) with Mechanical Convection The most versatile among refrigerated incubators for microorganisms: BINDER KB series refrigerated incubators control a temperature range from -5 °C to 100 °C. With advanced programming functions, the unit offers extensive capabilities and ensures repeatable test results. • Electronically controlled APT.line™ preheating chamber and patented DCT™ cooling system ensure temperature accuracy and reproducibility during both heating and cooling • Temperature range: -5 °C to 100 °C • MP controller with 2 programs of 10 segments each, or optionally 1 program with 20 segments • Integrated weekly timer with real-time function • Adjustable ramping function via program editor • Digital temperature setting with tenth-degree precision • Adjustable fan speed • Operating hour indicator • Independent, adjustable class 3.1 temperature safety device ensuring full chamber over-temperature protection, with visual and acoustic temperature alarm • Internal glass door • RS 422 interface for APT-COM™ DataControlSystem communication software Hodpox A Etlofx Ab Sjfd • Adjustable print intervals • 4 casters (2 with brakes) • Cable access port with silicone plug, Ø 30 mm, left side • 2 stainless steel racks

Būklė: beveik kaip naujas (naudotas), Binder BD240 / Binder BD 240 – Laboratorinis inkubatorius Naudotas, geros būklės, patikrintas ir veikiantis. Inkubatorius su gravitacine konvekcija. Specializuotas įrenginys organizmų inkubavimui bei mikrobiologiniam šildymui ir kondicionavimui. Hfjdox A Eluspfx Ab Sjd Temperatūros diapazonas: nuo 5°C virš aplinkos temperatūros iki 100°C. Kaina už vienetą, yra 6 vnt.

Būklė: labai geros būklės (naudotas), Zwick / Roell Model: Z020 Allround-Line BT1-FR020TN.A50 Zwick / Roell Materials Testing Machine 20 kN Tensile & Compression Test testXpert III For sale is a high-quality Zwick / Roell materials testing machine for professional tensile and compression testing of materials and components. The machine is suitable for metals, plastics, rubber, and many other materials and is typically used in laboratories, quality assurance, research, and education. Control is via PC with Zwick/Roell testXpert III software (data carrier & documentation included). Technical Data: Rated test force: 20 kN Test direction: Tensile & compression Power supply: 230 V / 50–60 Hz / 1-phase Hedpfx Abjx Up Igj Ssfd Power consumption: approx. 2.1 kVA Weight: approx. 150–180 kg Dimensions: approx. 856 × 650 × 1,545–2,114 mm Technical data (from documentation & nameplate) Mechanics / Testing Rated force: 20 kN Test direction: Tensile & compression Max. test frequency: 0.5 Hz Crosshead: servo-electrical Positioning accuracy: < 1 µm Speed range: 0.0005 – 1,000 mm/min Dimensions & Weight Overall height: approx. 1,545 – 2,114 mm (depending on crosshead position) Overall width: approx. 856 mm Overall depth: approx. 650 mm Test area width: 440 mm Weight: approx. 150 kg (base unit) approx. 180 kg with typical equipment Electrical Data Power supply: 230 V AC Phases: 1-phase (1PH, N, PE) Mains frequency: 50 / 60 Hz Current draw: approx. 8–10 A Power consumption: approx. 2.1 kVA Socket: Schuko (CEE 7) Measuring & Control Electronics Internal data acquisition: 500 Hz Data transmission to PC: adjustable 10–100 Hz Interface: RS232 (COM) Electronics enclosure protection rating: IP32 Important note: "The table shown in the photos is not included in the sale." Condition: used Scope of delivery: (see photo) Zwick / Roell materials testing machine (20 kN) Electronics unit PC workstation (monitor and PC; condition as per photos) 2 measuring modules (Delock units) Zwick/Roell testXpert III software (data carrier) Original operating and technical documentation Various connection and interface cables (Subject to changes and errors in technical data. All information without guarantee!) For further questions, feel free to contact us by phone.

Gamybos metai: 2015, būklė: naudotas, Funkcionalumas: visiškai funkcionalus, mašinos/transporto priemonės numeris: B115.0548, Caracteristici tehnice: Specificații principale Gama de temperatură: +20 °C până la +300 °C Control temperatură: microprocesor PID cu afișaj SINGLE (ecran color TFT) Senzor: 1 × Pt100 DIN Clasa A în circuit cu 4 fire Precizia setării: Până la 99,9 °C: 0,1 °C Hfodpfsyana Dsx Ab Sed De la 100 °C: 0,5 °C Volum: 32 litri Dimensiuni interioare (L × Î × A): 400 × 320 × 250 mm Dimensiuni exterioare (L × Î × A): 585 × 704 × 434 mm Capacitate maximă încărcare: 60 kg (20 kg pe raft) Număr de rafturi: 1 grătar din inox (maxim 3 posibile) Ventilație & Încălzire Tip convecție: Circulație naturală a aerului Sistem de încălzire: Încălzire pe suprafață mare, pe patru laturi Control aer proaspăt: Clapetă de aer reglabilă electronic Racord evacuare: Cu clapetă de reglare Electric & Mediu Alimentare electrică: 230 V, 50/60 Hz, aprox. 1600 W Disponibilă și versiune 115 V Interval temperatură ambient: +5 °C până la +40 °C Toleranță umiditate: max. 80% RH, fără condens Altitudine maximă: până la 2.000 m peste nivelul mării Control & Siguranță Temporizator: 1 minut până la 99 zile Funcție SET POINT WAIT: Cronometrul pornește doar după atingerea temperaturii setate Protecție la supratemperatură: Monitor electronic Limitator mecanic (TB), DIN 12880 Clasa 1 Calibrare: 3 valori de temperatură la alegere Documentație: Software Atmo CONTROL prin USB sau Ethernet Limbi: engleză, germană, spaniolă, franceză Construcție & Materiale Interior: oțel inoxidabil electrolustruit Exterior: oțel inox texturat (spate: oțel zincat) Ușă: complet izolată, cu închidere în două puncte Greutate: Net: ~45 kg Cuptorul este ideal pentru procese de uscare, încălzire, îmbătrânire și întărire în cercetare, controlul calității și laboratoare industriale Stare utilaj: FUNCȚIONAL

Būklė: beveik kaip naujas (naudotas), Gamybos metai: 2025, Įrenginys kaip naujas, 2025 metų, eksdemo Gamintojas: Binder Modelis: KBF 115 Gamybos metai: 2025 Tipas: Klimato kamera su pastoviomis sąlygomis Temperatūros diapazonas: 0-70°C Drėgmės diapazonas: 10–80% Drėgmės kontrolė: drėgmės jutiklis + garinis drėkinimas Galia: 2 kW Talpa: 115 litrų Ethernet jungtis Vidiniai matmenys: 60 × 35 × 45 cm Išoriniai matmenys: 70 × 103 × 90 cm Hfodpsxyy Hhofx Ab Ssd

Būklė: labai geros būklės (naudotas), Vötsch Model: VC³ 4018/S Vötsch VC³ 4018/S Climate Test Chamber for Li-Ion CO/CO₂ −42 to +150°C, 400 V, Air-cooled For sale is a temperature and climate test chamber from the renowned German manufacturer Vötsch Industrietechnik GmbH, model VC³ 4018/S, year of manufacture 2012. The chamber is specially equipped for testing lithium-ion batteries and features CO monitoring as well as CO₂ inertization to enhance operational safety. Important note: Due to this safety equipment, the test chamber's software limits the temperature range to −42°C to +150°C. This chamber is ideally suited for: - Li-Ion battery tests - Electronics and assembly testing - Temperature and climate stress tests - Research & development and quality assurance tasks Technical data: - Test chamber dimensions: Width 580 mm x Depth 450 mm x Height 750 mm - External dimensions: Width 870 mm x Depth 1550 mm x Height 1800 mm - Test chamber volume: 190 liters - Standard cable port: - R1: Ø 125 mm - L1: Ø 50 mm Specifications for temperature testing: - Temperature range: -42°C to +150°C - Temporal temperature deviation: ± 0.1 to ± 0.5 K - Spatial temperature uniformity: ± 0.5 to ± 1.5 K - Temperature change rate: - Heating: 4 K/min - Cooling: 4 K/min - Max. heat compensation: 2300 W Specifications for climate testing: - Temperature range: +10 to +95°C - Dew point range: -3 to +94°C - Humidity range: 10 to 98% r.h. - Temporal temperature deviation: ± 0.1 to ± 0.3 K - Spatial temperature uniformity: ± 0.5 K - Temporal humidity deviation: ± 1 to ± 3% r.h. - Heat compensation: 400 W Operating details: - Test chamber lighting: Halogen bulb 2 x 24V, 50W - 3/N/PE AC 400V ±10%, 50 Hz - Rated power: 4.1 kW - Rated current: 14 A Hjdpfx Abex Slm Ho Sefd Refrigerant: R-404A Weight: 470 kg Buyer information for your security: The following steps are carried out in advance on our offered chambers: 1. Functional check and replacement of necessary components 2. New filling with legally compliant refrigerant if needed 3. Leak test with certificate 4. Once tests are passed, the chambers undergo a documented trial run Condition: used Delivery scope: (see image) (Specifications subject to change and error!) Further questions? Please contact us by phone.

Gamybos metai: 1970, būklė: naudotas, Techninės detalės: x eiga: - mm y eiga: - mm z eiga: - mm Ruošinio svoris: 800 kg Mašinos svoris apytiksliai: 0,75 kg Mašinos matmenys apytiksliai Ilg x Pl x Aukšt: 1,2 x 0,08 x 2,0 m Hjdpfxexu Dwyo Ab Sofd Įpjovinės smūginės tvirtumo matas parodo, kiek medžiaga atspari staigiems apkrovimams, ypač kai prieš tai buvo įpjova (įpjovinis smūgis). Tai ypač taikoma metalų lūžio tvirtumo įvertinimui dinaminio apkrovimo metu.

Būklė: labai geros būklės (naudotas), Here we offer a Heraeus air circulation dryer. Technical specifications UT 6760 Dimensions: External housing: width 1200 mm x height 1838 mm x depth 790 mm Internal dimensions: width 1000 mm x height 1319 mm x depth 522 mm Temperature range: 300°C Rated voltage: 3N/PE 50 Hz 400 V 9.6 A 6.3 kW Capacity: 689 liters Hfjdoup U T Uepfx Ab Sjd Empty weight: 241 kg Type: UT6760

Būklė: labai geros būklės (naudotas), The Thermo Scientific Heraeus Biofuge Primo R centrifuge enables both high-throughput and low-volume processing thanks to optional rotors and accessories, with a maximum rotational speed of up to 15,000 rpm. This compact, high-performance refrigerated centrifuge ensures efficient and flexible sample processing. Primo R features automatic rotor identification and imbalance detection with uniform temperature control. Primo R is ideally suited for small medical laboratories, biochemical and molecular biology research, and routine analyses in industrial labs. Typical applications include cell sedimentation (algae, yeast, bacteria, etc.), sedimentation of cell organelles and fragments, DNA sample and protein precipitate preparation, blood and urine analysis, as well as centrifugation of standard test series in microliter tubes. This refrigerated centrifuge is equipped with both a fixed-angle rotor and a swinging-bucket rotor. Technical specifications: Voltage: 220-240 V Current: 2.9 A Power: 490 W Maximum centrifuge speed: 15,000 rpm (adjustable in steps of 10) Minimum centrifuge speed: 300 rpm Maximum RFC: 21,855 g Temperature range: -9…40°C Noise level at maximum speed: < 60 dB Rotor recognition: automatic Imbalance detection: electronic Safety features: lid lock and blocking Rotor specification 1: Number: 7591 Type: swinging-bucket rotor Maximum speed: 4,000 rpm Maximum RCF: 2,585 g Maximum capacity: 4 x 100 mL. Hedpfx Aot Eva Ijb Sefd

Būklė: labai geros būklės (naudotas), Binder FED 400 laboratory drying oven Temperature range: from 5°C above ambient temperature up to 300°C – Classic.Line series - Stainless steel interior, powder-coated housing - Digital temperature setting in 1°C increments - Digital controller with integrated timer - Timer allows programming of start, stop, and holding time (temperature holding time: 0 to 99 hours 59 minutes) - APT.Line preheating system - Digitally adjustable fan speed - Class 2 temperature safety device (DIN 12880) with visual alarm - Two chrome-plated shelves included as standard Hodpfjxanx Ssx Ab Ssfd - Maximum number of shelves: 10 pcs - Maximum total load: 90 kg - Maximum shelf load: 35 kg - Overall dimensions including fittings and connections (L x H x W): 1235 x 1025 x 765 mm - Internal dimensions (L x H x W): 1000 x 800 x 510 mm - Computer interface: RS 422 - Net weight: 145 kg - Internal volume: 400 L - Power supply: 400 V

Gamybos metai: 2023, būklė: beveik kaip naujas (naudotas), SYNC Particle Size Analyzer Measurement method: laser diffraction (ISO 13320) + dynamic image analysis (ISO 13322-2) Version: 3R + L (three red lasers 780 nm + L camera 4.6-2000 µm) Measuring range: 0.02 – 2000 µm Dispersion: wet (FlowSync) + ultrasound Product page: Laser Diffraction and Image Analysis: SYNC :: For sale: Microtrac SYNC 3R L Particle Size Analyzer – Year of manufacture: 2023 We offer a state-of-the-art Microtrac SYNC 3R L particle size analyzer, an ex-demo unit in perfect technical and visual condition. The equipment has been tested and calibrated by the manufacturer and is ready for immediate operation. 🔍 Specification: • Model: Microtrac SYNC 3R L • Year of manufacture: 2023 • Condition: Ex-demo, like new • Tested and certified by the manufacturer Hfjdpfswtthusx Ab Ssd • Pre-installed original Microtrac FLEX software • Measurement by laser diffraction (LD) and dynamic light scattering (DLS) • Measuring range: from nanometres to micrometres • Automatic liquid feeder – 3R version (3 reactors) • Complete set, ready to use ✅ Advantages: • The device enables fast and accurate measurements in research & development as well as production laboratories. • Integration with software facilitates operation and data analysis. • No wear – the device was used for demonstration purposes only. 💼 Ideal for: • Pharmaceutical, chemical, materials, cosmetic industries • Research and development centers • Universities and analytical laboratories

Būklė: labai geros būklės (naudotas), veikimo valandos: 100 h, PERFECT CONDITION, purchased in December 2016 Used for approximately 100 hours Price new: 46,808 EUR The BINDER MKF series environmental simulation chamber is perfectly suited for all cold and heat testing based on recognized temperature and climate test standards in accordance with DIN and IEC norms. High operating comfort and comprehensive standard equipment offer clear advantages for everyday use. Key features Temperature range: -40 °C to 180 °C Humidity range: from 10 to 98% RH Built-in 20 L water reservoir 4 potential-free relay contacts Preheating chamber technology e™ Programmable anti-condensation protection for samples Heated observation window with internal LED lighting Humidity control with capacitive humidity sensor and steam humidification BINDER Multi Management Software APT-COM™ 4 Basic Edition Diagnostic system with optical and acoustic alarm Intuitive controller with touch screen, featuring segment and real-time programming Internal data logger; measurement values in open format, readable via USB 2 access ports with 80 mm silicone plugs, left and right side Independent, adjustable class 2 (DIN 12880) temperature safety device with optical alarm 4 castors, two with brakes 230 V socket on the right side panel Ramp function can be set Built-in line recorder Real-time clock Door heating Alarm notification in case of lack of water in the fresh water tank Hodpfx Aevldnqeb Sjfd 1 stainless steel wire shelf Leak protection for inlet and outlet hoses up to 1 m height Stainless steel interior Halogen-free refrigerant R-404A Cooling provided by compressor condenser unit

Būklė: beveik kaip naujas (naudotas), For sale: Binder FED 260 Laboratory Oven – Ex demo, year 2025 We offer a high-quality laboratory oven from Binder, model FED 260, coming from a demonstration (ex demo) display. The unit was manufactured in 2025 and is in virtually as-new condition – tested by the manufacturer and ready for immediate use. Technical specifications: • Model: FED 260 • Manufacturer: Binder (Germany) • Circulation type: Forced air circulation • Chamber capacity: 260 liters • Temperature range: +10°C above ambient temperature up to +300°C • Power supply: 230 V • Year of production: 2023 • Condition: Ex demo – the unit has only been used for demonstration purposes Advantages: • Excellent temperature uniformity throughout the chamber • Reliable and energy-efficient operation • Ideal for research laboratories, industrial facilities, and quality control institutes • Supplied with documentation and shelves Why choose this unit? Hfedpfxev Nw Ncs Ab Ssd • Attractive price compared to a new machine • No signs of use – unit looks like new • Immediate availability Transport across Europe can be arranged.

Gamybos metai: 2025, būklė: naudotas, Universal Testing Machine PM10 Force: 10 kN Crosshead stroke: 700 mm Test space: 400 mm Overall height: 1230 mm Weight: approx. 85 kg Position resolution: 0.01 mm Test speed: 1–500 mm / min Return speed: 700 mm / min Load cell: 10 kN Including evaluation electronics and basic software. Our testing machines can be operated in stand-alone mode using a numeric keypad, allowing for “quick testing” even without a PC. For tests that require data storage and curve recording, our basic software enables control and evaluation. This allows you to generate various test sequences and create a test report. You also have the option to further process the raw data in your own software. Optional: - Delivery & commissioning - DAkkS or factory calibration according to DIN EN ISO 7500-1 Hfjdpfoyc U Ugex Ab Sed - Grips and fixtures: Compression plates, bending fixtures, shear devices, wedge grips, scissor grips, peeling grips, screw grips, pneumatic grips, and hydraulic grips.

Gamybos metai: 1985, būklė: reikia remonto (naudotas), Funkcionalumas: ribota funkcionalumas, Schenk-Trebel Universal Testing Machine Type RME 250 kN • Load frame and drive unit manufactured by Schenk Trebel, year of construction 1985, total height approx. 3.3 m. Crosshead travel approx. 2 m • Modernization around end of 2003: Fitted with ZwickRoell's "testControl" electronic control system • Retrofit in 2010: Universal extensometer system MultiXtens by ZwickRoell, with swivel mount and two pairs of measuring probes (photo), as well as new testControl module • Info: The testControl module operates with the current software "testXpert III" from ZwickRoell (one license for testXpert III version 1.51 is included in the price) • Temperature chamber (photo) can be moved into the testing space of the machine, built in 2006 by RS-Simulatoren Prüf- & Messtechnik, heatable up to approx. 200°C; coolable with liquid nitrogen down to approx. –40°C • Load cells: 250 kN and 50 kN (currently installed, see machine photo); additionally: 5 kN, 1 kN, and 500 N (photo) • 2 wedge specimen grips (photo) Hfodpfx Ajyhb Rlsb Ssd Condition of the Machine The machine was in use for testing until early 2026. The following were used: The 50 kN load cell and the crosshead displacement transducer (both sensors: last calibrated 06.05.2024 incl. standard inspection work). A defect in the servo amplifier for the drive (a component in the testControl module) has led, since autumn 2025, to repeated loss of connection with the software and standstill of the drive until the hard- and software are restarted. The servo amplifier or the complete testControl module will need to be replaced (cost information available on request from the seller). The 250 kN load cell was last calibrated on 11.02.2021, but has not been used for measurements since then. The other load cells, the MultiXtens system, and the temperature chamber have not been used or calibrated in recent years. The two hydraulic clamping units visible in the photos installed in the machine will be removed and remain with the seller.

Būklė: labai geros būklės (naudotas), Espec Model: PL-2KPH ESPEC PL-2 KPH Climate Chambers, air cooled Temperature range: -40°C to +180°C Humidity range: approx. 10 to 98% RH Dependency on temperature range and humidity fluctuation: ± 2.5% RH over time ± 3.0% RH Internal dimensions: Width 500 × Height 750 × Depth 600 mm External dimensions: Width 910 × Height 1590 × Depth 973 mm Microprocessor control with 10 internationally pre-set test standards and 20 freely programmable memory slots, as well as integrated timer with program start/stop automation and error code display, programming via touch screen. Alarm indicator (acoustic and visual) Device protection in case of overtemperature Overtemperature protection with 2 switching contacts Test chamber lighting Operating hours counter Test chamber volume: 225 l Weight: 300 kg net Electrical connection: 400 V 3/N 50 Hz Plug: CEE 16 A, max. current consumption: 11.0 A Refrigerant: R404A Scope of delivery: Espec climate test chamber Important safety information for you as a buyer! The following points are carried out on all chambers offered by us prior to sale: 1. Functional test and replacement of necessary components 2. New refill with legally compliant refrigerant if necessary 3. Leak test with certificate 4. After successful inspection, the chambers undergo a documented test run. Condition: used Scope of delivery: see image Hfsdpfxox Iu I Ss Ab Ssd (Changes and errors in technical data and specifications reserved!) If you have further questions, we will be happy to answer them by phone.

Būklė: naujas, Gamybos metai: 2025, Funkcionalumas: visiškai funkcionalus, bendras svoris: 24 kg, bendras aukštis: 1 000 mm, bendras plotis: 330 mm, bendras ilgis: 530 mm, MultiTest 2.5dV yra vienas iš populiariausių tempimo ir spaudimo bandymų stendų. Šis testeris yra tvirtas, tikslus ir gali būti visiškai sukonfigūruotas pagal individualius poreikius su jėgos matavimo celėmis, spaustukais ir programine įranga. MultiTest 2.5dV galima komplektuoti su jėgos davikliais nuo 2 N iki 2,5 kN, priklausomai nuo pageidavimų. VectorPro Lite programinė įranga yra labai intuityvi, su aiškia vartotojo sąsaja. Dėl to testeris naudojamas ne tik laboratorijose ir matavimo kambariuose, bet ir tiesiogiai gamybos aplinkoje. Naudojant programinę įrangą, visi duomenys yra automatiškai išsaugomi ir vėliau gali būti peržiūrimi. Be programinės įrangos testeris veikia savarankiškai ir matavimo duomenis galima perduoti į kompiuterį įvairiais būdais. Kaina apima pasirinktinę jėgos celę, laidus, pristatymą Nyderlanduose ir Belgijoje, įrengimo bei apmokymų paslaugas. Suteikiama 2 metų garantija. VectorPro Lite programinės įrangos priemoka – 1 000 €, spaustukai į kainą neįskaičiuoti. Hodpfxjx Apnte Ab Sefd