The amino acids cysteine, serine, tellurocysteine, and selenocysteine are isoelectronic, at least with respect to valence electrons. The series stands out in the modern sports world respecting unique values like parity, equity, transparency and honesty. Dias, Dalton Trans. A 4-day stage race in the Azores at the end of October – Learn more. F - has 9 protons, a nuclear charge of +9. Question: Which Of The Following Ions Are Isoelectronic With The Bromide Ion? Rationale The CCIS series is devoted to the publication of proceedings of computer science conferences. The BCN-η monolayer (figure 1(f)) is.
This page is about the various possible words that rhymes or sounds like isoelectronic. Net dictionary. In many situations c (the center of the series) is equal to zero, for instance when considering a Maclaurin series. Online shopping for Amazon Original Series from a great selection at Movies & TV Store. The correct order of increasing length of their radii is (a)F- What is the isoelectronic principle?
Complete table of Serie A standings for the / Season, plus access to tables from past seasons and other Football leagues. The term means "equal electric" or "equal charge". &0183;&32;Isoelectronic means the same number of electrons, or the same electronic structure. The most accurate wave functions for the helium isoelectronic sequence require an explicit dependence on the interelectronic distance. · Created by Moisés Zamora. Isoelectric point: point 1. The metal cations follow Ne.
Kevin Miquel Sunn Enduro Factory Team 2870 points. The Golden Trail Series exists to celebrate and grow the sport of trail running. For example, the formula might be similar to the.
Take part in the Castle Triathlon, Run, Swim and Multisport Series at iconic castles across the UK, Ireland and France. 1) Which ion is smaller? Looking for the best shows on Netflix? Isoelectronic matricies--all isoelectronic species in a matrix defined by total electrons and valence electrons vary by progression in group number. Watch trailers & learn more. What are some examples of isoelectronic ions? Carbon-Based Materials for Thermoelectrics The term "isosteres" was defined for the first time (1919) by Langmuir in terms of isoelectronic or isosteric concept 6, 20 and thus emerged the concept of isosterism. And that&39;s the great thing about a brilliant series, once you finish one book, there&39;s always another.
By: Anthony T. Interpretation Translation isoelectronic ion. Temos todos os seriados que voc&234; gosta de assistir. Welcome to the official EA SPORTS FIFA Twitch channel.
We Can Be Heroes When alien invaders capture Earth’s superheroes, their kids must learn to work together to save their parents — and the planet. Its aim is to efficiently disseminate original research results in informatics in printed and electronic form. The console bundle is a good one. Cohen, Matthias Schef er Created Date: 6:36:08 PM. Concat (objs, axis = 0, join = 'outer', ignore_index = False, keys = None, levels = None, names = None, verify_integrity = False, sort = False, copy = True) source &182; Concatenate pandas objects along a particular axis with optional set logic along the other axes. Originally by Ranker TV.
A neutral Neon atom has 10 electrons and. So the vanadium is larger, and the manganese 2 plus is smaller. 等电子离子. &39;s chances of winning back-to-back NBA titles. Copland House plays a Tiny Desk (home) concert. Assistir S&233;ries Online sem travamento, o melhor site para assistir seriados on line, atualiza&231;&245;es di&225;ria.
But when we see isoelectronic series in the lecture, we note that the higher the positive charge, the smaller it&39;s going to be. Isoelectronic compounds rus. BIMMERPOST is the project of friends Mark and Jason who began this site as a small forum dedicated to the 3-Series.
That so many viewers latched on to Netflix docuseries Tiger King for that escapism earlier this year is one of the most startling. Izoelektroniniai junginiai statusas T sritis chemija apibrėžtis Vienodos elektroninės struktūros, bet turintys skirtingus atomus, junginiai. Description Type OS Version Date; Chipset INF Utility. Back to tab. — Louis Sachar, Holes. ; Genre: Zeitschriftenartikel; Im Druck ver&246;ffentlicht: 1971; Titel: OBSERVATION OF 23S-23P TRANSITIONS IN HE I ISOELECTRONIC SEQUENCE.
Five teens from Harlem become trapped in a nightmare when they&39;re falsely accused of a brutal attack in Central Park. The electron configuration of "Ni" is Ar 3d^8 4s^2. Which of the following ions are isoelectronic with the bromide ion? Noting or pertaining to atoms and ions having an equal number of electrons.
8k votes 4. Discover TV shows to watch - premieres, new episodes tonight and Certified Fresh shows as rated by critics. Since, we doubt that a simple substituent can give both effects, we hypothesize that the. All six of the ions contain 10 electrons in the 1s, 2s, and 2p orbitals, but the nuclear charge varies from +7 (N) to +13 (Al). 1039/D0DT01590C If you are not the author of this article and you wish to reproduce material from it in a third party. For many BMW buyers, though, entertaining handling manners are far more important than creature comforts. Creators Mickey Down and Konrad Kay present a new HBO series starring Myha’la Herrold. With Christian Serratos, Gabriel Chavarria, Ricardo Chavira, Noemi Gonzalez.
, if it is a metric space), then some series, the convergent series, can be interpreted as having a value in A, called the sum of the series. Isoelectronic ions are ions that have the same number of electrons. An anthology series centering on different characters and locations, including a house with a murderous past, an insane asylum, a witch coven, a freak show circus, a haunted hotel, a possessed farmhouse, a cult, the apocalypse, and a slasher summer camp. What is the formula of the ion? Title: Local Isoelectronic Reactivity of Solid Surfaces Author: Steffen Wilke and Morrel H. (they are in the same period or it is the preceeding noble gas. The HISTORY original series Vikings transports us to the brutal and mysterious world of Ragnar Lothbrok, a Viking warrior and farmer who yearns to explore--and raid--the distant shores across the.
Based on the true story. (Solution Download) isoelectronic. At an affordable price, the Road Series delivers the same quality expected from a Martin. Driver: Windows 7, 32-bit* Windows 7. Of ZnBeSe alloys at low Be concentrations. Isoelectronic species are known as atoms or ions that have the same number of electrons. 3) Briefly explain why the second ionization of Na (I2 = 4562 kJ/mol) is dramatically higher than the first (I1 = 496 kJ/mol). Thus: CO, N 2 and NO + are isoelectronic.
20 Best Book Series Ever It seems we all love a great series - we can&39;t get enough of the characters we fall in love with and can&39;t wait to see what happens next. An isoelectronic series is a group of atoms and/or ions all of which have the same number of electrons. Explore high-performance skincare for men at Lab Series. · Series.
Browse all Cinemax original series, stream episodes online plus extras such as trailers, recaps, behind the scenes and more. (1998)Angewandte Chemie International EditionBeitrag in einer Fachzeitschrift. Our Most Popular charts use data from the search behavior of IMDb&39;s more than 250 million monthly unique visitors to rank the hottest, most buzzed about movies and TV shows. Das gilt ebenso f&252;r die Kleinmotoren in unseren Schneefr&228;sen, Hochdruckreinigern, transportablen Stromerzeugern und auch in unseren Standby-Stromerzeugern. In the Values box, replace the cell reference with the defined name Sales. (broadcasting) A television or radio program which consists of several episodes that are broadcast in regular intervals. These include new titles built natively using the Xbox Series X|S development environment as well as previously released titles that have been rebuilt specifically for Xbox Series X|S. The isoelectronic pair is (a) Cl2O, ICl-2 (b) ICI-2, ClO2 (c) IF+2,I-3 (d) CIO-2,CIF+2.
Anitta: Made In Honório. The Peabody Award‑winning series profiling the men who have served as chief executive of the United States. With all these enthusiasts under one roof we decided to expand and add a dedicated blog of news and information. Stars: Lady Gaga, Kathy Bates, Angela Bassett, Sarah Paulson. Isoelectronic: Atoms, ions, or molecules which have an equal number of valence electrons and the same atom connectivity. And, with Smart Delivery games, you buy a digital game once and get the best version of that game for the console you’re playing on. Five years after the initial series, we re-evaluate the problems of maternal and child undernutrition and also examine the growing problems of overweight and obesity for women and children, and their consequences in low-income and middle-income countries. Atitikmenys: angl.
In mathematics, a telescoping series is a series whose partial sums eventually only have a finite number of terms after cancellation. See more videos for Isoelectronic. Drivers with top-five NASCAR Cup Series finishes in Twenty-seven drivers tallied at least one top-five finish during the NASCAR Cup Series season. Experience the speed and performance of a next-gen all-digital console at an accessible price point. Blue Note Records. Check out the most popular TV shows on IMDb. Изоэлектронные соединения. Movies, TV shows, specials and more, it’s all tailored specifically to you.
ดูซีรี่ส์เกาหลี kserie ซีรี่ส์เกาหลี ละครเกาหลี ซีรี่ส์เกาหลี. He, Li+, O^2-, Rb+, Se^2-, F-, Be^2+, Y^3, Mg^2+ HINT: Use a periodic table to determine the atomic number of the atom. For more tutorials please subscribe to our channel. Support on the go.
You can get an ion that is isoelectronic with neon by either "OXIDATION" or "REDUCTION. This series features Volko Ruhnke's game system presenting modern (Andean Abyss, Cuba Libre, A Distant Plain, Fire in the Lake, & Colonial Twilight), historic (Liberty or Death), and ancient (Falling Sky & Pendragon) guerrilla warfare and COunterINsurgencies around the world. Interest-ingly, the PL data give good evidence for both a change in the band gap and an isoelectronic bound exciton. Ca 2+ Ba 2+ Sr 2+ Se 2-Rb + S 2-Expert Answer. Isoelectronic Configurations.
&0183;&32;Isoelectronic ions are those ions which have same number of electrons in their respective ions. Dick and William Gibson, and in particular the 1982 film Blade Runner. Isoelectronic chemical species typically display similar chemical properties. Xbox Series X is compatible with standard standalone hard drive and products with the Designed for Xbox badge are supported by Xbox.
Ne, F – is an isoelectronic pair and their electronic configuration is 1s 2 2s 2 2p 6. GTWChamp's Rules. The Series 65 is an exam and securities license required by most US states for individuals to act as investment advisers.
Adjective isoelectronic designating or of any of two or more atoms which have the same number of electrons around the nucleus and similar spectral and physical properties 0; adjective isoelectronic (chemistry) (of two compounds) having the same electronic configuration although consisting of different elements. On the contrary, the BCN-η and BCN-θ monolayers are not composed of isoelectronic clusters to dehydronated benzene/borazine. There are many ions that are isoelectronic. Browse "Popular" to find your favorite show in the NBCUniversal family of networks on NBC.
Isoelectronic principle. Featuring new hit original series The Rook, Sweetbitter, Power, The Spanish Princess, Vida, Outlander, Wrong Man, American Gods, Now Apocalypse as well as Warriors of Liberty City, America to Me, Ash vs Evil Dead, Black Sails, Survivor&39;s Remorse, The. Jonathan Rhys Meyers stars in this original, history-based drama series as the young, vibrant King Henry VIII, a competitive and lustful monarch who navigates the intrigues of the English court and the human heart with equal vigor and justifiable suspicion. · Two or more are described as isoelectronic if they have the same number of electrons and the same structure, i. Previous question Next question Get more help from Chegg. Answer to Which one of the following is not isoelectronic with the others? Acknowledging the extraordinary talents of the man who defined an ageand the remarkable men and women who peopled and shaped it, the Napoleon Series seeks to promote the continued, scholarly exploration of that age.
High-performance engineering. " Angewandte Chemie (International Edition in English) 34. For example, CO, NO +, and N 2 are isoelectronic, whilst CH 3 COCH 3 and CH 3 N = NCH 3 are not. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. Featuring new hit original series The Rook, Sweetbitter, Power, The Spanish Princess, Vida, Outlander, Wrong Man, American Gods, Now Apocalypse as well as Warriors of Liberty City, America to Me, Ash vs Evil Dead, Black Sails, Survivor's Remorse, The. Challenging and fun races for newcomers, seasoned and pro athletes.
| Meaning, pronunciation, translations and examples. Consider the isoelectronic species, Na+, Mg2+, F and O2-. What is the chemical symbol of the noble gas this ion is isoelectronic with?
The AMD Embedded R-Series SoC (formerly codenamed “Merlin Falcon”) delivers astonishing graphics and HD multimedia processing performance – with true 4K decode and encode – via a sophisticated SoC architecture that integrates up to four of AMD’s latest high-performance “Excavator” x86 CPU cores with the latest AMD Radeon™ graphics and an I/O. Ions: isoelectronic Noble Gas. The series has just aired its third season, complete with jaw-dropping finale - and has been nominated for a slew of awards. World Series, in baseball, a postseason play-off series between champions of the two major professional baseball leagues of North America: the American League and the National League, which together constitute Major League Baseball. The site grew in popularity and the forums expanded to cover the entire BMW lineup of vehicles. Isoelectronic impurities in semiconductors Czaja, Wolfgang; Abstract. English-Chinese dictionary. List of Publication &187; Triphenylphosphonioacetylide: A species isoelectronic with isocyanidesBestmann HJ, Frank W, Moll C, et al.
C l O 3 −, S O 3 2 − are isoelectronic and isostructural. Carbon monoxide (CO) and dinitrogen (N 2 ) are isoelectronic. Information and translations of isoelectronic in the most comprehensive dictionary definitions resource on the web. See more results. Am beliebtesten ist der Rasenm&228;hermotor, der jedes Jahr eine Wartung und manchmal eine Reparatur erfordert. E² is an ongoing PBS series about the economies of being environmentally conscious with a combination of policy, technology and ingenuity from energy consumption to building efficiency It.
You have to count the number of electrons of N (nitrogen) atoms, the number of electrons of two O (oxygen) atoms, and the adjust for the negative charge of the ions. Isoelectronic species contain the same number of electrons Be2+ contains 2 electrons. Posted on. Power series are useful in mathematical analysis, where they arise as Taylor series of infinitely differentiable functions.
Discover the best Mystery Series in Best Sellers. The United Nations Treaty Series (UNTS) is a publication produced by the Secretariat of the United Nations containing all treaties and international agreements registered or filed and recorded by the Secretariat since 1945, pursuant to Article 102 of the Charter. Find and compare products, get support, and connect with Intel.
For example, CO, NO +. Group of answer choices. &0183;&32;Optimized for Xbox Series X|S Games featuring the Optimized for Xbox Series X|S icon will showcase unparalleled load-times, heightened visuals, and steadier framerates at up to 120FPS. A) Mn7+, V5+, Sc2+ b) Ar, Be2+, Cl - c) Ne, Li+, B3+ d) Cr6+, Ga3+, V5+ e) S2-, Ca2+, K+. JOIN OUR NEWSLETTER.
It is usually seen in constructions like "a series of," and like other count nouns, in these sentences the members of the group are pluralized while series itself remains singular. B-series burstable VMs are ideal for workloads that do not need the full performance of the CPU continuously, like web servers, small databases and development and test environments. Solution details: STATUS Answered QUALITY Approved ANSWER RATING. Find the top 100 most popular items in Amazon Kindle Store Best Sellers.
Consider the isoelectronic ions Cl- and K+. In photoluminescence spectra of these Al x Ga 1−x N layers, there is a gradual increase of the band gap and a smaller progressive shift of the position of blue emission band to the higher energies as the Al content increases. While the focus.
An (mono atomic) ion is called isoelectronic with another element (or ion) when it has the same number of electrons with it. Listen live & on-demand in the car, on our app or at home on connected devices. Kids Definition of series : a number of things or events arranged in order and connected by being alike in some way the third book in the series On either side of the rut were a series of ledges. Noun, plural se·ries. I need to find the bond order and also the most unstable compund of them all.
Wikipedia. Then you need to count the number of electrons in the given species NO₂⁻. Report 2 Answers By Expert Tutors Best Newest Oldest.
LubriSynHA Becomes Official Sponsor. A) $\ceXF^2+$ b) $\ceYF$ c) $\ceZF^1-$ When I try to solve for the unknown element I get this (I do not take in account only the valence electrons but all the electrons of the compound): a) $\ceOF^2+$ b) $\ceCF$ c. :. Georgina (Julia Stiles) has abandoned the cursed Riviera and started her life over, only to be thrown headlong into a dark and dangerous conspiracy. Introducing the Xbox Series S, the smallest, sleekest Xbox console ever.
Number and of atoms, but differ in some of the elements involved. Here’s everything you need to know about Apple Watch and the Apple Watch app on iPhone, straight from Apple. For example, CO, NO+, and N2 are isoelectronic, whilst CH3COCH3 and CH3N=NCH3 are not. More Isoelectronic videos. &0183;&32;Maternal and child undernutrition was the subject of a Series of papers in The Lancet in. Isoelectronic refers to two atoms, ions, or molecules that have the same electronic structure and the same number of valence electrons. Updated: Decem.
We&39;ve got 75 rhyming words for isoelectronic » What rhymes with isoelectronic? GT World Challenge Powered by AWS set for 29-event global schedule as Australia reveals calendar. Check out full episodes and video clips of most popular shows online.
Look no further, because Rotten Tomatoes has put together a list of the best original Netflix series available to watch right now, ranked according to the Tomatometer. ISOELECTRONIC Atoms or ions having same number of electrons or same electronic configuration, are called isoelectronic. In isoelectronic species, there the number of electrons would be equal but the elements would be different. Two or more molecular entities are described as isoelectronic if they have the same number of valence electrons and the same structure, i. Asked in Class XI Chemistry by rahul152 (-2,838 points) Consider the isoelectronic species, Na +, Mg 2+, F and O 2-. Definitions can sometimes be not as strict, sometimes requiring identity of the total electron count and with it the entire electron configuration. TCR New Zealand. Examples of Isoelectronic Elements and/or Ions.
In the Category (X) axis labels box, replace the cell reference with the defined name Date. For example Sodium ion is isoelectronic with Neon, Chloride ion is isoelectronic with Argon. W Series is a catalyst for change. Hence, the central atom in these undergoes s p 3 hybridization which. Learn more about the BMW 8 Series Coupe, Gran Coupe, Convertible, M8 Coupe, M8 Gran Coupe, and M8 Convertible.
Shop our high-tech collection of moisturizers, toners, skincare & men&39;s grooming products. The sequence in the table is an example. For the best experience, the 1TB Seagate Storage Expansion Card for Xbox Series X|S plugs into the back of the console via the dedicated storage expansion port and replicates the console’s custom SSD experience, providing additional game storage at the same. Hello Select your address All Hello, Sign in. As the positive charge of the nucleus. Browse all our shows. Und mit der Apple Watch Series 4 und neuer kannst du jederzeit ein Elektrokardiogramm (EKG) aufzeichnen. Late Tejano singer Selena as her dreams come true, and her family makes life-changing choices on the singer&39;s journey to success.
Neon, Ne; 1s2 2s2 2p6. The S series is still a rock 'n' roll version of a quick, graceful, and potentially lethal weapon. Wikipedia. Like our Facebook page for updates and new tutorials at: The term isoelectronic means same number of electrons. Na +, F - 2. Click the Series tab.
This ion is a(n) _____cationanion. Previously only available in printed format, the UNTS is now available as a fully-searchable on-line database. (Photo by Netflix) The 176 Best Netflix Series and Shows to Watch Right Now. K Ock O & Catz.
Item is Freigegeben einblenden: alle. More Isoelectronic images. We will also give many of the basic facts, properties and ways we can use to manipulate a series. The correct order of increasing length of their radii is. Tina Brooks - The Waiting Game LP (Tone Poet Series) . Follow a group of young graduates as they compete for a limited set of permanent positions at a top investment bank in London. More usually, definitions are broader, and may extend to allowing different numbers of.
Concat&182; pandas. Sequences and series are most useful when there is a formula for their terms. Series 24: The Series 24 is the securities license entitling the holder to supervise and manage branch activities. W Series: Racing's new game changer.
Both have ten valence electrons. Definition of isoelectronic in the Definitions. For the series case, the ratio of energy stored in springs is: =, but there is a relationship between x 1 and x 2 derived earlier, so we can plug that in: = =. Expert Answer 100% (19 ratings) Previous question Next question Get more help from Chegg. Isoelectronic species refers to the elements that have the same number of electrons. Isoelectronic Species: Isoelectronic species are those that have equal number of electrons present. PRICE: . Explore our extensive range of noise cancelling headphones, including Bluetooth & wireless, designed to help you enjoy your favorite music on the go.
Aluminum, the smallest of these ions, has the highest atomic number, 13. 23/24 January. John Scofield & Pat Metheny - I Can See Your House From Here 2LP (Blue Note Tone Poet Series) . Intel&174; USB 3. " Neon has (Z=10) has 8 valence electrons, and a full valence shell. &0183;&32;In this section we will formally define an infinite series.
So a higher nuclear charge pulling those electrons out in. The show is based on the real. 43v2) for Intel&174; 8 Series/C220 Series Chipset Families and 4th Generation Intel&174; Core™ Processor U-Series Platform. In the Series list, click Sales. Alright, Isoelectronic are those species (atoms)or molecules or ions; having same number of electrons in them.
Series definition, a group or a number of related or similar things, events, etc. Engelhardt, W. Download the SteelSeries Engine 3 software for the best gaming experience on Windows and Mac. Group Of Answer Choices Ca2+ Ba2+ Sr2+ Se2- Rb+ S2-This question hasn't been answered yet Ask an expert.
English-Bulgarian polytechnical dictionary. Strike is a British crime drama television programme based on the Cormoran Strike detective novels written by J. , the world-renowned series stretches from New York to California and hosts thousands of racers on foot and in the saddle.
SiriusXM brings you the widest variety in music, live sports, world-class news & nonstop laughs. Riviera: Series 3. Isabeau Courdurier. The series follows Spencer (Daniel Ezra), a talented football player who is yanked out of his Crenshaw high school to play for the more affluent Beverly Hills team. For the parallel case, = because the compressed distance of the springs is the same, this simplifies to =. Atoms, molecules as well as ions can all be isoelectronic to one another. TV and streaming series and movies have performed an enormous service this year in providing some much-needed escapism in a world crippled by a health crisis.
The coming-of-age story from Luca Guadagnino (Call Me by Your Name) follows two American teenagers as they encounter the highs and lows of youth while living on an American military base in Italy. The Maze Runner Series Complete Collection Boxed Set (5-Book) by James Dashner |. Before taking the Series 24 exam, a candidate must pass a prerequisite exam, the. Scrabble Points: 17. Check out the complete list.
THE PERIODIC TABLE 4. Find out more about the ground-breaking new racing series for women only and why we think it is a game changer. · Roxor Off-Road Vehicles Join World Series of Team Roping Sponsorship Team. * Apple Watch Series 6, Apple Watch SE, and Apple Watch Series 3 have a water resistance rating of 50 meters under ISO standard 22810:. S&233;ries Documentaires, feuilleton Suisse en g&233;n&233;rale ou autres docs festival, f&234;tes, &233;t&233;. Isoelectronic species For each of the species below, write out the full electronic configuration and then identify an anion and a cation which is isoelectronic with the initial species. When you have an isoelectronic series, but this is not isoelectronic.
· Isoelectronic refers to two atoms, ions, or molecules that have the same electronic structure and the same number of valence electrons. For example, the isoelectronic series of species with the neon closed-shell configuration (1s 2 2s 2 2p 6) is shown in Table \(\PageIndex3\). Star Trek: Voyager Rewatch: “Unforgettable”; Dawnshard Reread: Chapter 15 – Epilogue; Pinkerton’s Detergent Vs. From sitcoms to dramas to travel and talk shows, these are all the best programs on TV.
The Best Action TV Series Of All Time. The Eternal Bloodstain: Oscar Wilde’s “The Canterville. A succession of publications that present an extended narrative, such as a comic book series, or that have similar subjects or similar formats, such as a series of cookbooks. What are elements that are isoelectronic? ASTROPHYSICAL JOURNAL, 167 (1), 201-&. More Series images.
The B-Series provides these customers the ability to purchase a VM size with a price conscious baseline performance that allows the VM. WSC WORLD SPORTING CONSULTING LIMITED. Xbox All Access is your all-inclusive pass to Xbox and includes an Xbox Series S and 24 months of Xbox Game Pass Ultimate, with over 100 high-quality games and an EA Play.
Skip to main content. Exploring the lives. These workloads typically have burstable performance requirements. Because Xbox Series S is all digital, access your digital game library through the console and select the game you want to play. ¦ī·sō·i‚lek′trän·ik ′prin·sə·pəl (chemistry) The concept that molecules having the same number of electrons and the same number of atoms whose atomic masses are greater than that of hydrogen (heavy atoms) tend to have similar electronic structures, similar chemical properties, and heavy-atom geometries. The term "infinite series" is sometimes used to emphasize the fact that series contain an infinite number of terms. ,, 49, 8566 DOI: 10.
Integrate & differentiate power series Get 3 of 4 questions to level up! Learn more about the history and results of the World Series. This question was answered on:.
-> St eve underwear
-> Are sharks blind