Feb 18, 2022 · A hollow-core anti-resonant fiber for the THz regime is proposed and demonstrated. The proposed fiber is the hexagonal core shape which is directly extruded using a conventional 3D printer. Experimental results show that by using cyclic olefin copolymer (COC), the proposed fiber design provides a low attenuation of ∼3 dB∕m at ∼ 0.86 THz and ∼15 dB∕m at ∼ 0.42 THz. 4 days ago · 91thz.cc Quick Summary. ( Rescan now...) 91thz.cc traffic estimate is about 380 unique visitors and 4,940 pageviews per day. The approximated value of 91thz.cc is 87,600 USD. Every unique visitor makes about 13 pageviews on average. Alexa Traffic Rank estimates that 91thz.cc is ranked number 526 in the world, while most of its traffic comes ... 【歌詞】ライトの虹を 踏みながら 銀座の夜を ひらく薔薇 ああ 誰か呼ぶ 舞姫の その名はアンナ 東京アンナ 噂のアンナ 柔らな肌を 黒髪に 隠せ ... © 2024 九日烧官方网站 ... Skip to content Oct 9, 2007 · Abstract and Figures. Based on simplified rate equations, both static and dynamic behaviour have been studied in order to characterize 2.9THz QCLs that will be used in detection or transmission ... 1.9THz laser Pyro Voltage Amplifier Lock-in Amplifier Beam Splitter Silicon lens THz THz (a) Design of the THz antenna coupled graphene device. The graphene piece (black line) is positioned at the center. The 45 µm long slot at the location of the graphene channel is chosen such that it can accommodate well our target frequency at about 2THz Waveguide embedding of a double metal 1.9THz QCL into a split block with diagonal horn antenna Oct 1, 2016 · Biomedical Applications of Terahertz (THz) Spectroscopy. Due to the weak interactions including hydrogen bonds and van der Waals lying in the THz range, the low-frequency vibration and rotation of biomolecules could be probed by THz spectroscopy. (A) Absorption coefficients of the nucleobases adenosine (A), cytosine (C), guanine (G), and ... The same is true for many types of unit conversion (there are some expections, such as temperature). To convert Terahertz (THz) to Hertz (Hz), you just need to know that 1THz is …Sep 13, 2004 · We report the operation of a quantum cascade laser emitting at a 103μm wavelength (2.9THz). The active region is based on a bound-to-continuum design allowing a low parasitic leakage current, and a high upper-to-lower-state lifetime ratio. The latter is demonstrated by a pronounced decrease of the differential resistance at threshold, which is visible up to high temperatures, and by a weak ... Terahertz to Cycle/second. Terahertz to Wavelength In Exametres. Terahertz to Wavelength In Petametres. Terahertz to Wavelength In Terametres. Terahertz to Wavelength In Gigametres. Terahertz to Wavelength In Megametres. Terahertz to Wavelength In Kilometres. Terahertz to Wavelength In Hectometres. Terahertz to Wavelength In Dekametres. 1.9THz laser Pyro Voltage Amplifier Lock-in Amplifier Beam Splitter Silicon lens THz THz (a) Design of the THz antenna coupled graphene device. The graphene piece (black line) is positioned at the center. The 45 µm long slot at the location of the graphene channel is chosen such that it can accommodate well our target frequency at about 2THz Sep 13, 2004 · We report the operation of a quantum cascade laser emitting at a 103μm wavelength (2.9THz). The active region is based on a bound-to-continuum design allowing a low parasitic leakage current, and a high upper-to-lower-state lifetime ratio. The latter is demonstrated by a pronounced decrease of the differential resistance at threshold, which is visible up to high temperatures, and by a weak ... 影视 优酷 搜狐 腾讯 爱奇艺 乐视 土豆 酷6 PPTV. 搞笑 笑到爆 麻花 糗事 不得姐. 社区 猫扑 天涯 人人 贴吧. 交友 佳缘 百合 珍爱 有缘网. 音乐 酷我 QQ音乐 酷狗 唱吧. 小说 起点 宜搜 纵横 潇湘. …Aug 25, 2021 · Abstract. A Cylindrical Dielectric Resonator antenna (CDRA) along with silicon based Rectangular Dielectric Resonator (RDR) slab is proposed in this paper for terahertz …Mar 1, 2024 · In an effort to improve the SM characteristics and simplify these complex structures of hollow core THz waveguides, Sultana et al. incorporated a nested circle tube into a SM THz …4 days ago · 91thz.cc Quick Summary. ( Rescan now...) 91thz.cc traffic estimate is about 380 unique visitors and 4,940 pageviews per day. The approximated value of 91thz.cc is 87,600 USD. Every unique visitor makes about 13 pageviews on average. Alexa Traffic Rank estimates that 91thz.cc is ranked number 526 in the world, while most of its traffic comes ... Waveguide embedding of a double metal 1.9THz QCL into a split block with diagonal horn antenna © 2024 九日烧官方网站 ... Skip to content Mar 20, 2006 · 1.9. THz. quantum-cascade lasers with one-well injector. We report terahertz quantum-cascade lasers operating predominantly at 1.90 THz with side modes as low as 1.86 THz ( λ ≈ 161 μ m , ℏ ω ≈ 7.7 meV ). This is the longest wavelength to date of any solid-state laser that operates without assistance of a magnetic field. Jan 12, 2024 · Share your videos with friends, family, and the worldMar 19, 2024 · Hong Kong has fast-tracked into law domestic security legislation, prompting fresh warnings from the US, European Union and UK that the move could muzzle open discussion …More information from the unit converter. How many THz in 1 Hz? The answer is 1.0E-12. We assume you are converting between terahertz and hertz.You can view more details on each …Mar 15, 2019 · λ=C*T，λ =C/f. 其中，λ是波长， T 是周期， f 是频率，为 T 的倒数， C 是光速，根据光束恒定的价格， C=3 × 10^8m/s 。. 根据这个公式，就可以进行波长和频率的换算。. … What is the value of 32.9 thz in terms of hz? 32.9 thz is equal to 32900000000000 Hz. 5.8 A 32×32-Pixel 0.9THz Imager with Pixel-Parallel 12b VCO-Based ADC in 0.18μm CMOS Abstract: There are many compelling characteristics of signals in the terahertz band (100GHz …Apr 11, 2022 · A hollow-core anti-resonant fiber for the THz regime is proposed and demonstrated. The proposed fiber is the hexagonal core shape which is directly extruded …In this paper, we have proposed two types of cavity filters operating at around 0.9THz—the Photonic Bandgap (PBG) cavity filter [1,2] and the three-cavity dual mode filter[2,3]. The band …4 days ago · 91thz.cc Quick Summary. ( Rescan now...) 91thz.cc traffic estimate is about 380 unique visitors and 4,940 pageviews per day. The approximated value of 91thz.cc is 87,600 USD. Every unique visitor makes about 13 pageviews on average. Alexa Traffic Rank estimates that 91thz.cc is ranked number 526 in the world, while most of its traffic comes ... 1.9THz laser Pyro Voltage Amplifier Lock-in Amplifier Beam Splitter Silicon lens THz THz (a) Design of the THz antenna coupled graphene device. The graphene piece (black line) is positioned at the center. The 45 µm long slot at the location of the graphene channel is chosen such that it can accommodate well our target frequency at about 2THz © 2024 九日烧官方网站 ... Skip to content Example: convert 15 THz to nm: 15 THz = 299792.458 / 15 = 19986.163866667 nm. Convert Terahertz to Other Frequency Wavelength Units Feb 18, 2022 · A hollow-core anti-resonant fiber for the THz regime is proposed and demonstrated. The proposed fiber is the hexagonal core shape which is directly extruded using a conventional 3D printer. Experimental results show that by using cyclic olefin copolymer (COC), the proposed fiber design provides a low attenuation of ∼3 dB∕m at ∼ 0.86 THz and ∼15 dB∕m at ∼ 0.42 THz. = 0.0002 x 1012. = 20,000,000 hertz. ʄ (Hz) = ʄ (THz) x 1012 is the formula used by the converter when performing the conversions. To get the frequency in Hertz, we multiply the value in terahertz by 1012. The Terahertz to Hertz converter can only perform one calculation at a time. Micro-Electro-Mechanical Systems (MEMS) is a good choice for the fabrication of THz devices due to its low cost and high processing precision. In this paper, we have proposed two types of cavity filters operating at around 0.9THz—the Photonic Bandgap (PBG) cavity filter [1,2] and the three-cavity dual mode filter[2,3]. The band-pass filters are designed based on MEMS process and numerically ... 【歌詞】ライトの虹を 踏みながら 銀座の夜を ひらく薔薇 ああ 誰か呼ぶ 舞姫の その名はアンナ 東京アンナ 噂のアンナ 柔らな肌を 黒髪に 隠せ ... a spider on Taohuazu.com which can use for download or do more - Taohuazu/README.MD at master · zoneyaner/TaohuazuApr 5, 2022 · A hollow-core anti-resonant fiber for the THz regime is proposed and demonstrated. The proposed fiber is the hexagonal core shape which is directly extruded using a conventional 3D printer ... In questo video si continua a parlare di puro rotolamento ma questa volta viene esaminato il caso di un piano inclinato.http://www.ingcerroni.it/questioni-di... Apr 5, 2022 · optimized for thz guidance at 0.9thz. n att h awat p hanchat, 1,2,* w anvisa t a lata is o ng, 1,3. n icholas k l ok ko u, 1 r at c ha pak c hitaree, 2 v asilis. a postolopoulos, 4 m artynas b ... Waveguide embedding of a double metal 1.9THz QCL into a split block with diagonal horn antenna Aug 19, 2023 · A single-mode hollow-core anti-resonant (HC-AR) waveguide designed for low-loss terahertz (THz) wave propagation is fabricated by three-dimensional (3D) printing. Compared to similar structures reported recently, the rotating-nested semi-elliptical tubes (SETs) in the HC-AR THz waveguide cladding suppress multiple high-order modes (LP11, LP21, and LP02 modes) at the same time giving rise to ... Dec 3, 2023 · Here, an ultrabroadband (centre frequency of 3.9THz) and intense (peak electric field strength of 14.9MV/cm) THz pulse is utilized to excite a gravity-driven, free-flowing … The IF signal for STO has a bandwidth of 1 GHz and is centered at 1.5 GHz, appropriate for low noise operation of our HEBs. The IF output of each mixer is conveyed through 4 cm long, 0.035” diameter coaxial cable to low-noise (~7K), low-power (~5mW) SiGe amplifiers operating at a physical temperature of ~17K. Mar 20, 2006 · 1.9. THz. quantum-cascade lasers with one-well injector. We report terahertz quantum-cascade lasers operating predominantly at 1.90 THz with side modes as low as 1.86 THz ( λ ≈ 161 μ m , ℏ ω ≈ 7.7 meV ). This is the longest wavelength to date of any solid-state laser that operates without assistance of a magnetic field. Jun 13, 2003 · A planar-diode frequency tripler at 1.9THz Abstract: A fix-tuned 1.9 THz frequency tripler utilizing membrane based GaAs Schottky diodes has been designed and fabricated. …Sep 13, 2004 · Share. Tools. We report the operation of a quantum cascade laser emitting at a 103 μm 103 μ m wavelength (2.9 THz) ( 2.9 THz) . The active region is based on a bound-to … About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright ... Jun 13, 2003 · A planar-diode frequency tripler at 1.9THz Abstract: A fix-tuned 1.9 THz frequency tripler utilizing membrane based GaAs Schottky diodes has been designed and fabricated. …Mar 15, 2019 · λ=C*T，λ =C/f. 其中，λ是波长， T 是周期， f 是频率，为 T 的倒数， C 是光速，根据光束恒定的价格， C=3 × 10^8m/s 。. 根据这个公式，就可以进行波长和频率的换算。. … Here, an ultrabroadband (centre frequency of 3.9THz) and intense (peak electric field strength of 14.9MV/cm) THz pulse is utilized to excite a gravity-driven, free-flowing water film. The THz ... Research Article Vol. 28, No. 22/26 October 2020/Optics Express 32693 3.9 THz spatial filter based on a back-to-back Si-lens system YUNER GAN,1,2,6 BEHNAM MIRZAEI,1,3 SEBASTIAAN VAN DER POEL,4 ... Sep 13, 2004 · Share. Tools. We report the operation of a quantum cascade laser emitting at a 103 μm 103 μ m wavelength (2.9 THz) ( 2.9 THz) . The active region is based on a bound-to …Sep 13, 2004 · We report the operation of a quantum cascade laser emitting at a 103μm wavelength (2.9THz). The active region is based on a bound-to-continuum design allowing a low parasitic leakage current, and a high upper-to-lower-state lifetime ratio. The latter is demonstrated by a pronounced decrease of the differential resistance at threshold, which is visible up to high temperatures, and by a weak ... Mar 1, 2024 · Numerical results indicate that the single mode bandwidth with High Order Mode Extinction Ratio (HOMER) above 100 reaches up to 420 GHz covering the frequency range from 0.82 THz to 1.24 THz, in which the loss of Fundamental Mode (FM) remains below 0.05 dB/m. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright ... Dec 27, 2018 · The frequency of the plasma waves is 0.9THz which will travel a decay length of 44 nm (as compared to the 1.5μm channel length, L) from the source, which again confirms that the device is working as a broadband detector in overdamped plasma regime. Mar 1, 2024 · In an effort to improve the SM characteristics and simplify these complex structures of hollow core THz waveguides, Sultana et al. incorporated a nested circle tube into a SM THz …More information from the unit converter. How many THz in 1 Hz? The answer is 1.0E-12. We assume you are converting between terahertz and hertz.You can view more details on each …Jun 13, 2003 · A planar-diode frequency tripler at 1.9THz Abstract: A fix-tuned 1.9 THz frequency tripler utilizing membrane based GaAs Schottky diodes has been designed and fabricated. … The far field contributions from these four elements can be proved to be cancelled with each other, leading to significant reduction of radar cross sections as desired. The thickness of the sample is just 30μm and the simulated backward RCS reduction is above 10dB from 0.8 to 1.9THz. Mar 1, 2010 · Request PDF | On Mar 1, 2010, T. W. Crowe and others published Development and Characterization of a 1.9THz LO Source | Find, read and cite all the research you need on ResearchGate Jun 13, 2003 · A planar-diode frequency tripler at 1.9THz Abstract: A fix-tuned 1.9 THz frequency tripler utilizing membrane based GaAs Schottky diodes has been designed and fabricated. … Terahertz to Cycle/second. Terahertz to Wavelength In Exametres. Terahertz to Wavelength In Petametres. Terahertz to Wavelength In Terametres. Terahertz to Wavelength In Gigametres. Terahertz to Wavelength In Megametres. Terahertz to Wavelength In Kilometres. Terahertz to Wavelength In Hectometres. Terahertz to Wavelength In Dekametres. Mar 20, 2006 · 1.9. THz. quantum-cascade lasers with one-well injector. We report terahertz quantum-cascade lasers operating predominantly at 1.90 THz with side modes as low as 1.86 THz ( λ ≈ 161 μ m , ℏ ω ≈ 7.7 meV ). This is the longest wavelength to date of any solid-state laser that operates without assistance of a magnetic field. = 0.0002 x 1012. = 20,000,000 hertz. ʄ (Hz) = ʄ (THz) x 1012 is the formula used by the converter when performing the conversions. To get the frequency in Hertz, we multiply the value in terahertz by 1012. The Terahertz to Hertz converter can only perform one calculation at a time. Oct 30, 2015 · A multiflare angle horn is optimized with an in-house software using Body of Revolution finite-difference time-domain solver (BoR-FDTD) combined with a genetic algorithm (GA). This antenna is optimized to demonstrate low cross polarization, low side-lobe level, good return loss, and excellent beam circularity over the 1700-2100-GHz frequency range. A prototype with a directivity of 31.7 dBi ... Oct 30, 2015 · A multiflare angle horn is optimized with an in-house software using Body of Revolution finite-difference time-domain solver (BoR-FDTD) combined with a genetic algorithm (GA). This antenna is optimized to demonstrate low cross polarization, low side-lobe level, good return loss, and excellent beam circularity over the 1700-2100-GHz frequency range. A prototype with a directivity of 31.7 dBi ... Apr 5, 2022 · A hollow-core anti-resonant fiber for the THz regime is proposed and demonstrated. The proposed fiber is the hexagonal core shape which is directly extruded using a conventional 3D printer ... 5.8 A 32×32-Pixel 0.9THz Imager with Pixel-Parallel 12b VCO-Based ADC in 0.18μm CMOS Abstract: There are many compelling characteristics of signals in the terahertz band (100GHz …Taohuazu_桃花族论坛 - thzu.cc About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright ... Sep 13, 2004 · We report the operation of a quantum cascade laser emitting at a 103μm wavelength (2.9THz). The active region is based on a bound-to-continuum design allowing a … Waveguide embedding of a double metal 1.9THz QCL into a split block with diagonal horn antenna How to Convert Terahertz to Hertz. 1 THz = 1000000000000 Hz 1 Hz = 1.0E-12 THz. Example: convert 15 THz to Hz: 15 THz = 15 × 1000000000000 Hz = 15000000000000 Hz. Convert … 【歌詞】ライトの虹を 踏みながら 銀座の夜を ひらく薔薇 ああ 誰か呼ぶ 舞姫の その名はアンナ 東京アンナ 噂のアンナ 柔らな肌を 黒髪に 隠せ ... In this paper, we have proposed two types of cavity filters operating at around 0.9THz—the Photonic Bandgap (PBG) cavity filter [1,2] and the three-cavity dual mode filter[2,3]. The band …Oct 9, 2007 · Abstract and Figures. Based on simplified rate equations, both static and dynamic behaviour have been studied in order to characterize 2.9THz QCLs that will be used in detection or transmission ... Mar 15, 2019 · λ=C*T，λ =C/f. 其中，λ是波长， T 是周期， f 是频率，为 T 的倒数， C 是光速，根据光束恒定的价格， C=3 × 10^8m/s 。. 根据这个公式，就可以进行波长和频率的换算。. …Aug 19, 2023 · A single-mode hollow-core anti-resonant (HC-AR) waveguide designed for low-loss terahertz (THz) wave propagation is fabricated by three-dimensional (3D) printing. Compared to similar structures reported recently, the rotating-nested semi-elliptical tubes (SETs) in the HC-AR THz waveguide cladding suppress multiple high-order modes (LP11, LP21, and LP02 modes) at the same time giving rise to ... Mar 16, 2011 · 추자현 씨는 개인적인 기념 용도로 촬영해 소장한 누드사진이 유출되자 큰 충격을 받은 것으로 알려졌는데요, 법률 대리인 측에서도 성명을 발표해 ... The far field contributions from these four elements can be proved to be cancelled with each other, leading to significant reduction of radar cross sections as desired. The thickness of the sample is just 30μm and the simulated backward RCS reduction is above 10dB from 0.8 to 1.9THz. Oct 9, 2007 · Abstract and Figures. Based on simplified rate equations, both static and dynamic behaviour have been studied in order to characterize 2.9THz QCLs that will be used in detection or transmission ... Feb 18, 2022 · A hollow-core anti-resonant fiber for the THz regime is proposed and demonstrated. The proposed fiber is the hexagonal core shape which is directly extruded using a conventional 3D printer. Experimental results show that by using cyclic olefin copolymer (COC), the proposed fiber design provides a low attenuation of ∼3 dB∕m at ∼ 0.86 THz and ∼15 dB∕m at ∼ 0.42 THz. Mar 1, 2024 · Numerical results indicate that the single mode bandwidth with High Order Mode Extinction Ratio (HOMER) above 100 reaches up to 420 GHz covering the frequency range from 0.82 THz to 1.24 THz, in which the loss of Fundamental Mode (FM) remains below 0.05 dB/m. Sep 13, 2004 · We report the operation of a quantum cascade laser emitting at a 103μm wavelength (2.9THz). The active region is based on a bound-to-continuum design allowing a low parasitic leakage current, and a high upper-to-lower-state lifetime ratio. The latter is demonstrated by a pronounced decrease of the differential resistance at threshold, which is visible up to high temperatures, and by a weak ... Fig. 1. The measured output power of a series of WR0.51x3 triplers to ~1.9THz at room temperature. Each of these triplers was pumped by the same lower frequency driver. Although the power level achieved for the best builds is very useful for atmospheric purposes, the variation from build to build is indicative of the challenges of developing such 1. The measured output power of a series of WR0.51x3 triplers to ~1.9THz at room temperature. Each of these triplers was pumped by the same lower frequency driver. Although the power level achieved for the best builds is very useful for atmospheric purposes, the variation from build to build is indicative of the challenges of developing such ... Apr 5, 2022 · A hollow-core anti-resonant fiber for the THz regime is proposed and demonstrated. The proposed fiber is the hexagonal core shape which is directly extruded using a conventional 3D printer ... Dec 21, 2022 · A pair of PC enthusiasts have managed to overclock Intel’s recently-released Core i9-13900K processor to 9GHz, achieving a new world record. Overclocking experts Jon Sandström and Pieter ...
= 0.0002 x 1012. = 20,000,000 hertz. ʄ (Hz) = ʄ (THz) x 1012 is the formula used by the converter when performing the conversions. To get the frequency in Hertz, we multiply the value in terahertz by 1012. The Terahertz to Hertz converter can only perform one calculation at a time. . Chilib
Taohuazu_桃花族论坛 - thzu.cc Here, an ultrabroadband (centre frequency of 3.9THz) and intense (peak electric field strength of 14.9MV/cm) THz pulse is utilized to excite a gravity-driven, free-flowing water film. The THz ... 1.9THz laser Pyro Voltage Amplifier Lock-in Amplifier Beam Splitter Silicon lens THz THz (a) Design of the THz antenna coupled graphene device. The graphene piece (black line) is positioned at the center. The 45 µm long slot at the location of the graphene channel is chosen such that it can accommodate well our target frequency at about 2THz Fig. 1. The measured output power of a series of WR0.51x3 triplers to ~1.9THz at room temperature. Each of these triplers was pumped by the same lower frequency driver. Although the power level achieved for the best builds is very useful for atmospheric purposes, the variation from build to build is indicative of the challenges of developing such Oct 30, 2015 · A multiflare angle horn is optimized with an in-house software using Body of Revolution finite-difference time-domain solver (BoR-FDTD) combined with a genetic algorithm (GA). This antenna is optimized to demonstrate low cross polarization, low side-lobe level, good return loss, and excellent beam circularity over the 1700-2100-GHz frequency range. A prototype with a directivity of 31.7 dBi ... Advanced Physics. Advanced Physics questions and answers. (a) The vibrational frequency of H2 is 131.9 THz. What is H2's zero-point energy? What is the minimum absorption energy for H2 vibrations? What is H2 force constant? Note: for two masses connected by a spring, the appropriate harmonic oscillator mass is: u m m2/ (m1 m2), which yields w k/u. Mar 16, 2011 · 추자현 씨는 개인적인 기념 용도로 촬영해 소장한 누드사진이 유출되자 큰 충격을 받은 것으로 알려졌는데요, 법률 대리인 측에서도 성명을 발표해 ... The far field contributions from these four elements can be proved to be cancelled with each other, leading to significant reduction of radar cross sections as desired. The thickness of the sample is just 30μm and the simulated backward RCS reduction is above 10dB from 0.8 to 1.9THz. Mar 1, 2024 · Numerical results indicate that the single mode bandwidth with High Order Mode Extinction Ratio (HOMER) above 100 reaches up to 420 GHz covering the frequency range from 0.82 THz to 1.24 THz, in which the loss of Fundamental Mode (FM) remains below 0.05 dB/m. Oct 30, 2015 · A multiflare angle horn is optimized with an in-house software using Body of Revolution finite-difference time-domain solver (BoR-FDTD) combined with a genetic algorithm (GA). This antenna is optimized to demonstrate low cross polarization, low side-lobe level, good return loss, and excellent beam circularity over the 1700-2100-GHz frequency range. A prototype with a directivity of 31.7 dBi ... 4 days ago · 91thz.cc Quick Summary. ( Rescan now...) 91thz.cc traffic estimate is about 380 unique visitors and 4,940 pageviews per day. The approximated value of 91thz.cc is 87,600 USD. Every unique visitor makes about 13 pageviews on average. Alexa Traffic Rank estimates that 91thz.cc is ranked number 526 in the world, while most of its traffic comes ... About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright ... .