Ecosystem

an ecological community that includes all organisms which occur naturally within a specific area.

Taken from Dictionary of Science

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The term ecosystem refers to the combined physical and biological components of an environment. An ecosystem is generally an area within the natural environment in which physical (abiotic) factors of the environment, such as rocks and soil, function together along with interdependent (biotic) organisms, such as plants and animals, within the same habitat. Ecosystems can be permanent or temporary. Ecosystems usually form a number of food webs.

Taken from Wikipedia

Decibel

a unit for measuring the level of sound which has the symbol dB.

Taken from Dictionary of Science

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The decibel (dB) is a logarithmic unit of measurement that expresses the magnitude of a physical quantity (usually power or intensity) relative to a specified or implied reference level. Since it expresses a ratio of two quantities with the same unit, it is a dimensionless unit. A decibel is one tenth of a bel, a seldom-used unit.

The decibel is widely known as a measure of sound pressure level, but is also used for a wide variety of other measurements in science and engineering (particularly acoustics, electronics, and control theory) and other disciplines. It confers a number of advantages, such as the ability to conveniently represent very large or small numbers, a logarithmic scaling that roughly corresponds to the human perception of sound and light, and the ability to carry out multiplication of ratios by simple addition and subtraction.

The decibel symbol is often qualified with a suffix, which indicates which reference quantity or frequency weighting function has been used. For example, "dBm" indicates that the reference quantity is one milliwatt, while "dBu" is referenced to 0.775 volts RMS.

The definitions of the decibel and bel use base-10 logarithms. For a similar unit using natural logarithms to base e, see neper.

Taken from Wikipedia

Calorimetry

the discovery of certain thermal properties of substances such as calorific value, specific heat or latent heat in physics and chemistry. The instrument used is called a calorimeter and it consists essentially of apparatus which allows the substance to be burnt and the heat transferred to a surrounding body of water, enabling the rise in temperature and therefore the heat output to be measured.

Taken from Dictionary of Science

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Calorimetry is the science of measuring the heat of chemical reactions or physical changes. Calorimetry involves the use of a calorimeter. The word calorimetry is derived from the Latin word calor, meaning heat. Scottish physician and scientist Joseph Black, who was the first to recognize the distinction between heat and temperature, is said to be the founder of calorimetry.

Indirect calorimetry calculates heat that living organisms produce from their production of carbon dioxide and nitrogen waste (frequently ammonia in aquatic organisms, or urea in terrestrial ones), OR from their consumption of oxygen. Lavoisier noted in 1780 that heat production can be predicted from oxygen consumption this way, using multiple regression. The Dynamic Energy Budget theory explains why this procedure is correct. Of course, heat generated by living organisms may also be measured by direct calorimetry, in which the entire organism is placed inside the calorimeter for the measurement.

The specific heat formula is as follows:

where

q is energy, or heat,

m is mass,

c is specific heat capacity,

ΔT is change in temperature.

Taken from Wikipedia

Ballistics

the study of the flight path of an object which is being influenced by GRAVITY as it moves. It is applied to bullets, rockets, missiles etc.

Taken from Dictionary of Science

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Ballistics (gr. βάλλειν ('ba'llein'), "throw") is the science of mechanics that deals with the flight, behavior, and effects of projectiles, especially bullets, gravity bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance.

A ballistic body is a body which is free to move, behave, and be modified in appearance, contour, or texture by ambient conditions, substances, or forces, as by the pressure of gases in a gun, by rifling in a barrel, by gravity, by temperature, or by air particles. A ballistic missile is a missile only guided during the relatively brief initial powered phase of flight and its course is subsequently governed by the laws of classical mechanics.

In the field of forensic science, forensic ballistics is the science of analyzing firearm usage in crimes.

Taken from Wikipedia

Acetic Acid

a chemical compound, more correctly called ethanoic acid, which is the acid found in vinegar. It is present as a solution in water of strength 3 to 6%, in other words there are 3 to 6 parts of acetic acid in 100 parts of water. The chemical formula for acetic acid is CH₃COOH which contains two carbon atoms bonded together; to one are bonded three hydrogen atoms and to the other one one oxygen and one hydroxyl group (OH). Acetic acid is made from ethanol or acetylene.

Taken from Dictionary of Science

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Acetic acid, CH₃COOH, also known as ethanoic acid, is an organic acid, which gives vinegar its sour taste and pungent smell. It is a weak acid, in that it is only a partially dissociated acid in an aqueous solution. Pure, water-free acetic acid (glacial acetic acid) is a colourless liquid that absorbs water from the environment (hygroscopy), and freezes at 16.5 °C (62 °F) to a colourless crystalline solid. The pure acid, and concentrated solutions, are dangerously corrosive.

Acetic acid is one of the simplest carboxylic acids. It is an important chemical reagent and industrial chemical, used in the production of polyethylene terephthalate mainly used in soft drink bottles; cellulose acetate, mainly for photographic film; and polyvinyl acetate for wood glue, as well as synthetic fibres and fabrics. In households, diluted acetic acid is often used in descaling agents. In the food industry acetic acid is used under the food additive code E260 as an acidity regulator and as a condiment on chips.

The global demand of acetic acid is around 6.5 million tonnes per year (Mt/a), of which approximately 1.5 Mt/a is met by recycling; the remainder is manufactured from petrochemical feedstocks or from biological sources. Dilute acetic acid produced by natural fermentation is called vinegar.

Taken from Wikipedia

Zoology

a branch of biology that involves the study of animals. Subjects studied include anatomy, physiology, embryology, evolution, and the geographical distribution of animals.

Taken from Dictionary of Science

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Zoology, (officially pronounced /zoʊˈɑlədʒɪ/, colloquially pronounced /zuːˈɑlədʒɪ/) occasionally also spelled zoölogy, is the branch of biology that focuses on the structure, function, behavior, and evolution of animals.

Taken from Wikipedia

The Joy of Cooking

By Bernie Franco

The drama princess discovers her passion for food and cooking.

Her interest in cooking was born at the same time that she started acting. Early in her showbiz career, she would often hitch a ride with the catering service bound for wherever they were shooting. "Wala akong sasakyan at sumasabay ako sa catering. Nagigising ako sa amoy ng ginigisang gulay at sa tunog ng mga kutsilyo hanggang sa nagkaroon na ako ng urge na tumulong," she shares.

In between takes, she would help the cooks with their work. "Ako yung naglalagay ng rekado at eight years old, ah!" she relates. "Hanggang sa natututo na ako. Nakikihalo na rin ako, tumutulong. Iba ang nararamdaman kong sense of achievement." Slowly--and despite her young age--Judai was seriously developing her interest in cooking that, years later, would turn into a full-blown passion.

It also runs in the blood. Her parents know how to cook. "Si Daddy, marunong magluto kasi Kapampangan siya. Ang mommy, magaling talagang magluto," she reveals.

Her helper and relative, Ate Binay--a good cook herself--has been a very big influence on her too. Judai saw how Ate Binay managed the kitchen. "Sumasama ako sa kanya sa palengke. Kaya hanggang ngayon, nare-relax ako kapag nasa palengke ako," she says. "Kasi bumabalik ako sa pagkabata."

As her showbiz career took shape, so did her love for cooking. It was therapy for her, a relief from the pressures of showbiz work. "Napansin ko sa sarili ko na kapag nagluluto ako, wala akong ibang iniisip. Hindi ako nasi-stress," the actress enthuses. "Pag humawak na ako ng kutsilyo at humarap sa kalan, wala nang puwedeng umistorbo sa akin."

Even when the demands of work have doubled, Judai never lost her zeal for cooking. "I would always find time. Kahit madaling-araw pa 'yan, magluluto ako. Kakailanganin kong magluto talaga," she emphasizes.

It was also in cooking that Judai found comfort in times of trouble. As a result, "Mas lalo akong na-in-love sa pagluluto 'nung time na nagkaka-problema ako."

Judai has friends in the industry who helped fuel this passion. "Kay Mother Biboy Arboleda (StarStudio Philippines Editor-in-Chief) ako tumatakbo pag may problema ako." Judai goes to Biboy's house where he prepares "comfort food" for her. "Ipagluluto lang niya ako ng pasta. Kinabukasan, lulutuin ko na yun."

Mylene Dizon introduced her to herbal ingredients for healthy eating. Maricel Soriano taught her a secret recipe for roast chicken. "Na-introduce ako sa malaking mundo ng pagluluto dahil sa kanila," she exclaims.

Judai's specialty is Japanese fried rice. It served to introduce her passion to her colleagues in ABS-CBN. "Nilako siya. Nagkaroon na ako ng buffet nito para sa ibang tao," she jokes. Among them were Boy Abunda, Kris Aquino and Star Cinema Managing Director Malou N. Santos. "Pagkatapos n'on, nagkaroon na ng request for me to cook Japanese fried rice, kaya tuwang-tuwa ako. It's another part of me which I could share with people." Some friends even request her to cook it for them when they're sick.

Judai's cooking charms work even on her fiance, actor Ryan Agoncillo. In their case, the cliché holds true: the way to a man's heart is his stomach. "Nagkaroon kami ng sukiyaki tapa with fried rice at nag-come up ako ng sarili kong recipe ng salpicao na nagustuhan niya. Puwede na nga akong mag-come up ng sarili kong cookbook dahil sa kakaluto ko."

And like the way she excels in acting, Judai has never settled for mediocrity in her cooking. She is now on her second course at the Center for Culinary Asian Studies. "I'm taking up Asian Cooking. Ito yung Asian introduction to everything: Thai, Chinese, Vietnamese and Japanese. 'Yung puspusang pag-aaral talaga on how they do it sa country nila."

Her first few attempts at cooking did not always turn out perfectly, but she struggled-- and is still struggling-- to excel. Learning how to cook is a process. "Of course, may mga palpak pa rin. hindi naman porke't nag-culinary ka, perfect na lahat. Ang dami kong moments na hindi ko puwedeng ma-satisfy sa ginagawa ko kasi ako, bini-beat ko pa rin ang sariling time ko, eh," she explains. "Gagawin ko yung best ko na ma-beat yung nauna kong record time."

Judai intends to go abroad to further her culinary studies so she become a full-fledged chef. "Ito lang ang matatapos kong kurso if ever. Not everybody has a passion for cooking. Pero ako, ito naman talaga ang passion ko, eh. Many people want to cook but not everybody has the talent."

Taken from Starstudio magazine: Judy Ann Santos special issue

Treasures of the Heart: Judy Ann's 30 Most Special Things and Places

1 security pillows

Dalawang unan palagi dapat meron sa kotse ko. Hindi ako kumportable umalis pag wala akong dalang unan. Feeling ko may hindi magandang mangyayari sa akin.

2 necklace from Ryan

Para sa isang babaeng marami-rami na rin naman ang pinagdaanan sa aspeto ng puso, malaking bagay ang ipagkatiwala sa iyo ang kuwintas na nagmula pa sa nanay ng lalakeng minamahal mo. Simbolo 'yon ng pagmamahal at higit sa lahat, ng pagtitiwala. Nung gabing isinuot ni Ryan sa akin ang kuwintas, halo-halo ang pakiramdam ko. May saya, may kaba, pero higit sa lahat, napaka-haba ng buhok ko, umabot hanggang Pagudpod 'nung oras na yon ang buhok ko!

3 my cell phone

High school ako unang nagka-cellphone. Dinaig ako ng mga kabataan today na 11 years old pa lang yata, o mas bata pa, may cellphone na! Pero yung hindi high-tech na unit ang sa akin. Madalas ko kasing nawawala eh. Importante lang na may pang-text at pantawag ako.

4 our Oris and Tissot watches

Yung Oris watch, gift ni Ryan sa akin nung Christmas. His & Hers watches kami. Yung Tissot, binili namin sa Prague nung nag-Europe trip kami.

5 chef's garb

Madalas sa mga taping o shooting ko, iba't-ibang characters ang ginagampanan ko. May doctor, teacher, abogado at kung ano-ano pa. Nung mag-e-enroll ako sa culinary school, ang isa sa mga pinaka-aabangan kong makuha nung araw ng klase namin ay ang uniform namin.Una kong tinignan ang nakaburdang pangalan sa garb ko. Pagsuot ko ng uniform ko, katumbas pala ng pakiramdam na 'yun sa akin ay ang pagtanggap ng acting award. May konting kaba dahil siguro excited ako at babalik ako sa pag-aaral. Pero higit sa kung ano pa man, kapag suot ko ang garb ko, ibang tao ako, hindi ako artista. Isang tao na gusto maging chef, isang tao na bumubuo at tinutupad ang isang bagong pangarap.

6 Chiang Mai

Christmas gift ni Ryan sa akin two years ago. Nag-cooking school ako, at saka pumangas kami ng pagkarami-rami. Tahimik yung lugar, parang Baguio at napaka-friendly ng mga tao. Nag-bungee jumping kami ni Rye dun, na muntik ng malagot ang tonsils ko kakasigaw. Pagkatapos nun, bingi na si Rye.

7 Tagaytay

Kapg punong-puno na ng intriga ang buhay ko, o kaya pagod na pagod lang ako, pumupunta ako ng Tagaytay. Minsan, mag-isa lang ako nag-da-drive papunta dun. Wala lang, para maiba lang ang ginagawa ko. Kadalasan, gusto ko lang ng tahimik at walang kausap; minsan naman, kasama ko ang mga kaibigan ko, pero hindi rin kami nag-uusap. Ganyan ang trip ko noon.

8 Our Lady of Manaoag

We always go here nila Mommy kapag magpapasalamat or to simply just pray. Tuwing may bagong sasakyan, sa Manaoag namin pinapa-bless palagi. Hanggang ngayon, devotee kami ng Our Lady of Manaoag. Dito rin kami nagkakilala ni Fr. Sonny Ramirez. We became good friends, and until now, palagi siyang nag-ce-celebrate ng Thanksgiving Mass every Christmas.

9 Infant Jesus of Pampanga

Si Tito Alfie ang nag-introduce sa akin sa Infant Jesus sa Pampanga. Seven Sundays na magkakasunod akong nagpunta to say my Novena. After the seventh Sunday, nag-dere-derecho na blessings ko. Sa kanya rin ako humiling ng tamang lalaking mamahalin at makakasama habang buhay -- and after ilang years, dumating si Ryan sa buhay ko.

10 Antipolo

Dito kami lumaking magkakapatid; dito nabuo ang childhood ko, kaya siguro wala akong regrets sa buhay. Na-experience ko kung paano maging bata. Nagkaroon din ako ng chance na makapag-shooting ng pelikula sa dating school ko, kasama mga classmates ko nung Elementary.

11 Nintendo-DS

Maliban sa niregalo ni Rye (Ryan Agoncillo) sa akin yun, siya lang ang kasa-kasama kokahit saan. Pang-lilbang ko, saka ni Yohan.

12 my chef's kit

Kapag artista ka, importante ang kikay kit mo, ang make-up kit. Pero kapag nag-chef ka, ang pinaka-importanteng bitbit mo ay mga kutsilyo, pang-hasa at kung ano-ano pang gamit sa pagluluto. Simula nung mag-aral ako, hindi pwedeng mawala sa paningin ko ang tool kit ko at ang Chef's Kit ko.

13 my acting awards

Isa sila sa pinaka-magandang nangyari sa akin. Nagkaroon ng marka lahat ng pinaghirapan ko sa more than 20 years ko sa industriya. Excited akong ipakita sila sa mga anak ko at magiging apo.

14 perfume

Para rin syang lampin sa akin. Tatlong klaseng pabango palagi ang dala ko: may pang-formal, hindi masyadong pormal at saka pang araw-araw lang. Turo din ni Ate Mary sa akin yun. Dapat palagi akong mabango.

15 Café Ysabel

Obviously, dito nabuo at nag-umpisa ang mga pangarap ko maging chef. Hindi pa naman ako ganap na chef talaga -- struggling pa lang! Parang opisina ko na rin siya, kasi kapag may meetings, interviews at kung ano-ano pa, dito na lang namin ginagawa. Bakit? Eh kasi nag o-OJT ako dun.

16 pink Vespa

Birthday gift ni Rye sa akin two years ago ito. First motor ko at Vespa pa. After niya ako turuan mag-vespa for Super G., niregalo na niya yung Vespa sa akin.

17 the Roadtrek

Eto ang dream car ko talaga. Bata pa lang ako, gustong-gusto ko talagang makasakay sa sasakyang parang bahay. (Yun ang tawag ko sa Roadtrek nung bata pa ako). Nung finally, nabili ko na siya, tatlong araw akong hindi makatulog at tatlong linggo akong palaging nakangiti. Reward ko siya sa sarili ko sa walang humpay kong pagtatrabaho. Mas lalo naman din akong nagsipag magtrabaho. Nabenta ko na siya ngayon, pero masaya rin ako kasi natupad ko ang isa sa mga pinangarap ko.

18 gumamit ng lampin

I started using this nung nakasama ko si Ate Mary (Maricel Soriano). Malambot raw kasi yung tela, saka mabilis maka-absorb ng pawis. Mula high school hanggang ngayon, may lampin pa rin akong dala kahit saan ako magpunta. Sa ibang tao, kapag nakakalimutan nila magsuot ng watch, pakiramdam nila, hubad sila. Ganoon ako sa lampin.

19 Batangas

Mahilig kami ni Rye sa beach. Kapag may butas sa schedule namin, pumupunta kami ng Batangas to unwind and relax. Minsan nag-da-dive kami doon with our friends, tapos kwentuhan lang, ang sarap, at ang saya.

20 Baguio

Madalas din akong mag-road trip sa Baguio. Day trip lang, lalo na kapag wala akong pera. Aakyat ako ng madaling-araw, kakain ng breakfast sa Café by the Ruins, mag-ta-take out ng kamote bread at rice wine. Tambay ng konti, punta sa palengke, tapos uwi na. Ganun lang ka-simple ang trip ko: bugbugin ang katawan ko sa biyahe.

21 Greenbelt 5

First time akong maka-experience ng movie marathon sa buong buhay ko. Dalawang movies ang pinanood namin ni Rye nang tanghaling tapat. Sabi niya kasi masyado na akong maraming nami-miss na pelikula! Mula nun, updated na ako sa lahat ng movies na lumalabas.

22 NAPA Valley

Sa sobrang kagustuhan kong makakita ng maraming winery, dinala kami ni Ryan ng mga kaibigan namin sa Napa Valley. Na-in love ako sa lugar at doon ko nakita ang culinary school na papasukan ko.

23 Casa Marcos

Nung bata palang ako, madalas kami ni Ate Binay na naka-tambay sa Regal Films. Nasa Valencia pa ang office ng Regal noon, at madalas kong marinig noon na pupunta sila sa Casa Marcos para kumain ng pandesal at mushroom soup. Tumatak sa utak ko 'yon. Nung nakuha ko yung tseke ko sa Regal, pina-rediscount namin ni Ate Binay agad yung tseke sa NR Marketing, tapos pumunta kaming Casa Marcos para kumain ng pandesal at mushroom soup. Mula noon hanggang ngayon, para sa akin iyon ang pinakamasarap na pandesal at sabaw na natikman ko. Kaya siguro kapag naka-break ako sa diyeta, hindi pwedeng mawala ang pandesal sa listahan ng una kong kakainin.

24 my Rosary

Bata pa lang ako, palagi na 'kong may dalang rosary kahit saan ako magpunta. Kapag nabubwisit ako, or nalulungkot ako, rosary ang hawak ko. At kahit anong simbahan ang puntahan ko, I always make it a point na makabili ng rosary for myself, family and friends.

25 grocery - shopping

Maliban sa pagbili ng mga kailangan sa bahay, pupunta ako ng grocery kapag pagod ako sa trabaho. Meaning, segue ako sa taping at shooting. Ang ending, makakapagluto ako ng pagkain na pwede ng pumasa pang buffet.

26 my favorite footwear

Hindi ako pwedeng umalis ng bahay ng walang Chucks sa van. Mas madalas akong mag-Chucks kesa mag-slippers kapag nasa labas ako.

27 a Tiffany necklace from Ate Sharon

Nagkaron kami ng guesting sa isang talk show to promote Magkapatid. Sa end ng guesting, magbibigayan kami ng gift sa isa't-isa. Ang binigay ko, maraming ballpen na Hello Kitty at saka pencil case (mahilig kasi si Ate magsulat). Ang gift ni Ate, itong necklace. Iyak ako ng iyak. Kailangan pa ba I-explain kung bakit? Hindi na, di ba?

28 a cross from Jerusalem

Itong cross na ito, galing Jerusalem. Pasalubong ni Mommy sa aming tatlo, sa mga apo niya, pati kay Rye, nung nagpunta si Mommy ng Holy Land. Ang purpose daw nito, to keep us safe from harm and accidents.

29 identical rings from Magic Mountain

Sa bawa't biyahe namin ni Rye, may tinatawag kaming "To mark the moment". These rings ang unang-unang nabili namin bilang first time namin together na pumunta sa iisang amusement park and ito rin ang singsing na si Kuja Jeff ang nag-suggest sa amin kung ano ang ipapa-engrave namin. Priceless para sa akin ang moment na yon, na may singsing kami ni Rye at nakita ko ang dalawang lalake sa buhay ko na magkasundong-magkasundo. Nung time na 'yun, nakita ko kung gaano ako ka-suwerte magkaroon ng mga taong pumuprotekta, nagmamahal at nakakaintindi sa akin.

30 my engagement ring

Kailangan ko pa bang I-explain?

Taken from Starstudio magazine: Judy Ann Santos special issue

Young's Modulus

Young's modulus (E) relates the STRESS and STRAIN in a solid (usually wire) using the following formula:

E = stress/strain = σ/ε

where σ = Force/Area and E = Change in Length/Length

Young's modulus has units of newtons per metre squared (Nm^-2) and is calculated only when the material is under elastic conditions, i.e., the force applied does not exceed the elastic limit and cause deformation.

Taken from Dictionary of Science

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In solid mechanics, Young's modulus (E) is a measure of the stiffness of an isotropic elastic material. It is also known as the Young modulus, modulus of elasticity, elastic modulus (though Young's modulus is actually one of several elastic moduli such as the bulk modulus and the shear modulus) or tensile modulus. It is defined as the ratio of the uniaxial stress over the uniaxial strain in the range of stress in which Hooke's Law holds. This can be experimentally determined from the slope of a stress-strain curve created during tensile tests conducted on a sample of the material.

Young's modulus is named after Thomas Young, the 19th century British scientist. However, the concept was developed in 1727 by Leonhard Euler, and the first experiments that used the concept of Young's modulus in its current form were performed by the Italian scientist Giordano Riccati in 1782 — predating Young's work by 25 years.

Taken from Wikipedia

X-Ray Crystallography

(or X-ray diffraction---XRD - crystallography) a technique used in geology to identify minerals, and biology or chemistry to work out the structure of complex molecules. It involves directing a beam of X-rays at a CRYSTAL and the rays are diffracted off the planes of atoms in the crystal. By repeating the procedure and then calculating the spacing between atomic planes, a representation of the crystal's structure can be determined.

Taken from Dictionary of Science

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X-ray crystallography is a method of determining the arrangement of atoms within a crystal, in which a beam of X-rays strikes a crystal and diffracts into many specific directions. From the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their disorder and various other information.

Since many materials can form crystals — such as salts, metals, minerals, semiconductors, as well as various inorganic, organic and biological molecules — X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences among various materials, especially minerals and alloys. The method also revealed the structure and functioning of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. X-ray crystallography is still the chief method for characterizing the atomic structure of new materials and in discerning materials that appear similar by other experiments. X-ray crystal structures can also account for unusual electronic or elastic properties of a material, shed light on chemical interactions and processes, or serve as the basis for designing pharmaceuticals against diseases.

In an X-ray diffraction measurement, a crystal is mounted on a goniometer and gradually rotated while being bombarded with X-rays, producing a diffraction pattern of regularly spaced spots known as reflections. The two-dimensional images taken at different rotations are converted into a three-dimensional model of the density of electrons within the crystal using the mathematical method of Fourier transforms, combined with chemical data known for the sample. Poor resolution (fuzziness) or even errors may result if the crystals are too small, or not uniform enough in their internal makeup.

X-ray crystallography is related to several other methods for determining atomic structures. Similar diffraction patterns can be produced by scattering electrons or neutrons, which are likewise interpreted as a Fourier transform. If single crystals of sufficient size cannot be obtained, various other X-ray methods can be applied to obtain less detailed information; such methods include fiber diffraction, powder diffraction and small-angle X-ray scattering (SAXS). In all these methods, the scattering is elastic; the scattered X-rays have the same wavelength as the incoming X-ray. By contrast, inelastic X-ray scattering methods are useful in studying excitations of the sample, rather than the distribution of its atoms.

Taken from Wikipedia