2012年5月22日 星期二
Time(1010522)
Rethinking the Movie Masterpieces: Richard Corliss Expands TIME’s List of Cinematic Greats
TIME's critic updates our All-TIME 100 list of the greatest films made since 1923 — the beginning of TIME — with 20 new entries
Alexandria … Why?
By Richard Corliss
May 17, 2012
For decades, at film festivals, Egyptian director Youssef Chahine (1926–2008) was the prime representative of an entire continent, Africa, and a world religion, Islam — though his family was Christian and his ancestors came from Greece and Lebanon. Both a nationalist and an internationalist, Chahine loved Hollywood movies (as a young man he studied acting at the Pasadena Playhouse) and learned as much from their robust pace as he did from the gritty humanism of Italian neorealist films and the romantic sweep of Indian cinema in its postwar golden age.
Chahine’s near masterpiece Alexandria …Why?, the first of his Alexandria quartet of films, is set in Egypt during World War II, when Arab nationalists were killing English soldiers — anything to get the British empire out of Palestine. But this sprawling epic is mainly the story of a young man, transparently Chahine himself, who loves Shakespeare and American movies. At the end, he sails into New York Harbor as Glenn Miller’s “Moonlight Serenade” plays on the soundtrack. Below him are some Hasidic Jews; above is the Statue of Liberty, which has morphed into a heavyset actress he knew back home and is exploding in a ribald laugh. The collision of world cultures was rarely defined with such brio.
2012年3月26日 星期一
環境微生物學(Environmental Microbiology)-蔡竹固老師
第一章、緒論
http://web.ncyu.edu.tw/~jgtsay/jg4-13-1.html
第二章、微生物之分類
http://web.ncyu.edu.tw/~jgtsay/jg4-13-2.html
第三章、微生物之培養與鑑定
http://web.ncyu.edu.tw/~jgtsay/jg4-13-3.html
第四章、微生物營養代謝與能量
http://web.ncyu.edu.tw/~jgtsay/jg4-13-4.html
第九章 污水處理微生物
http://web.ncyu.edu.tw/~jgtsay/jg4-13-8.html
生物復育(Bioremediation)
http://web.ncyu.edu.tw/~jgtsay/jg4-13-12.html
參考書目:
1. Madigan, M. T., Martinko, J. M., and Parker, J. 2003. Brock Biology of Microorganisms. Tenth edition. Prentice-Hall, Inc.1019p.
2. Maier, R. M., Pepper, I. L., and Gerba, C. P. 2000. Environmental Microbiology. Academic Press, New York, 585p.
3. Pepper, I. L., Gerba, C. P., and Brendecke, J. W. 2000. Environmental Microbiology A Laboratory Manual. Academic Press, New York, 175p.
4. 江晃榮編著。2001。環保微生物學。復文書局。臺南。328頁。
5. 吳錦、劉洪歧、吳淑岱譯(都留信也著)。1997。環境微生物 再版。科技圖書公司。臺北。298頁。
6. 張仁福。1997。環境微生物學。文京圖書公司。臺北。635頁。
7. 徐振盛、李夢諺。1995。環境微生物學。淑馨出版社。207頁。
8. 吳先琪、王美雪、施養信、劉泰銘譯(Bitton, Gabriel原著)。2000。廢水微生物學。國立編譯館。臺北市。740頁。
http://web.ncyu.edu.tw/~jgtsay/jg4-13-1.html
第二章、微生物之分類
http://web.ncyu.edu.tw/~jgtsay/jg4-13-2.html
第三章、微生物之培養與鑑定
http://web.ncyu.edu.tw/~jgtsay/jg4-13-3.html
第四章、微生物營養代謝與能量
http://web.ncyu.edu.tw/~jgtsay/jg4-13-4.html
第九章 污水處理微生物
http://web.ncyu.edu.tw/~jgtsay/jg4-13-8.html
生物復育(Bioremediation)
http://web.ncyu.edu.tw/~jgtsay/jg4-13-12.html
參考書目:
1. Madigan, M. T., Martinko, J. M., and Parker, J. 2003. Brock Biology of Microorganisms. Tenth edition. Prentice-Hall, Inc.1019p.
2. Maier, R. M., Pepper, I. L., and Gerba, C. P. 2000. Environmental Microbiology. Academic Press, New York, 585p.
3. Pepper, I. L., Gerba, C. P., and Brendecke, J. W. 2000. Environmental Microbiology A Laboratory Manual. Academic Press, New York, 175p.
4. 江晃榮編著。2001。環保微生物學。復文書局。臺南。328頁。
5. 吳錦、劉洪歧、吳淑岱譯(都留信也著)。1997。環境微生物 再版。科技圖書公司。臺北。298頁。
6. 張仁福。1997。環境微生物學。文京圖書公司。臺北。635頁。
7. 徐振盛、李夢諺。1995。環境微生物學。淑馨出版社。207頁。
8. 吳先琪、王美雪、施養信、劉泰銘譯(Bitton, Gabriel原著)。2000。廢水微生物學。國立編譯館。臺北市。740頁。
2012年3月25日 星期日
國考須加強(高中化學)
1.可見光波長：390~750nm
h: Planck constant =6.626*10^-34(J*S)
2.雷德堡(Rydberg's)方程式：
v=R(1/n1^2-1/n2^2)
R: 3.287*10^15 (S^-1)
萊曼(Lyman) 紫外光 n→1
巴耳麥(Balmer) 可見光及紫外光 n→2
h: Planck constant =6.626*10^-34(J*S)
2.雷德堡(Rydberg's)方程式：
v=R(1/n1^2-1/n2^2)
R: 3.287*10^15 (S^-1)
萊曼(Lyman) 紫外光 n→1
巴耳麥(Balmer) 可見光及紫外光 n→2
2011年1月17日 星期一
防爆外殼(NEMA VS IP)
NEMA Types – Definitions Pertaining to Nonhazardous Locations
Enclosures for Electrical Equipment
An enclosure is a surrounding case constructed to provide protection from accidental contact with the enclosed equipment and to provide protection to the enclosed equipment from specified environmental conditions. A brief description of the more common types of enclosures used by the electrical industry follows.
Type 1 Enclosure: Intended for indoor use primarily to provide protection against contact with enclosed equipment.
Type 2 Enclosure: Intended for indoor use primarily to provide a degree of protection against limited amounts of falling water and dirt.
Type 3 Enclosure: Intended for outdoor use primarily to provide a degree of protection against wind-blown dust, rain, sleet and external ice formation.
Type 3R Enclosure: Intended for outdoor use primarily to provide a degree of protection against falling rain, sleet and external ice formation.
Type 3S Enclosure: Intended for outdoor use primarily to provide a degree of protection against windblown dust, rain, and sleet, and to provide for operation of external mechanism when ice laden.
Type 3X Enclosure: Intended for outdoor use primarily to provide a degree of protection against corrosion, wind-blown dust, rain, sleet and external ice formation.
Type 3SX Enclosure: Intended for outdoor use primarily to provide a degree of protection against corrosion, wind-blown dust, rain, and sleet, and to provide for operation of external mechanism when ice laden.
Type 4 Enclosure: Intended for indoor or outdoor use primarily to provide a degree of protection against wind-blown dust and rain, splashing water and hose-directed water.
Type 4X Enclosure: Intended for indoor or outdoor use primarily to provide a degree of protection against corrosion, wind-blown dust and rain, splashing water and hose-directed water.
Type 6 Enclosure: Intended for indoor or outdoor use primarily to avoid a degree of protection against contact with enclosed equipment, falling dirt, hose-directed water, entry of water during occasional temporary submersion at a limited depth and external ice formation.
Type 6P Enclosure: Intended for indoor or outdoor use primarily to provide a degree of protection against contact with enclosed equipment, falling dirt, hose-directed water, entry of water during prolonged submersion at a limited depth and external ice formation.
Type 12 Enclosure: Intended for indoor use primarily to provide a degree of protection against dust, falling dirt and dripping noncorrosive liquids.
Type 13 Enclosure: Intended for indoor use primarily to provide a degree of protection against dust, spraying of water, oil and noncorrosive coolant.
IP (Ingress Protection) Rating for Equipment and Enclosures
A two-digit number (as specified in Australian Standards AS60529 and EN60529) is used to provide an IP Rating to a piece of electronic equipment or to an enclosure for electronic equipment.
The two digits represent three different forms of environmental influence:
The first digit represents protection against ingress of solid objects
The second digit represents protection against ingress of liquids
The larger the value of each digit, the greater the protection from that influence. As an example, a product rated as IP57 would be better protected against environmental factors than another similar product that was only rated as IP43. Our Gel Connectors are rated at IP67 (totally protected against dust ingress and withstands immersion up to a depth of 1 metre).
Value First Digit Second Digit
Protection against ingress Protection against ingress
of solids of liquids
0 No protection No protection
1 Protected against solid Protected against vertically
objects over 50mm e.g. falling drops of water.
hands, large tools
2 Protected against solid objects over Protected against direct sprays of water up to 15°
12mm e.g. hands, large tools from vertical.
3 Protected against solid objects over Protected against direct sprays of water up to 60°
2.5mm e.g. wire, small tools from vertical.
4 Protected against solid objects over Protected against water sprayed from any direction.
1.0mm e.g. wires Limited ingress permitted.
5 Limited protection against dust ingress Protected against low pressure water jets from any
(no harmful deposit) direction. Limited ingress permitted.
6 Totally protected against dust ingress. Protected against high pressure water jets from any
direction. Limited ingress permitted.
7 - Protected against immersion between 15cm and 1M.
8 - Protected against long periods of immersion under pressure.
9 - -
Enclosures for Electrical Equipment
An enclosure is a surrounding case constructed to provide protection from accidental contact with the enclosed equipment and to provide protection to the enclosed equipment from specified environmental conditions. A brief description of the more common types of enclosures used by the electrical industry follows.
Type 1 Enclosure: Intended for indoor use primarily to provide protection against contact with enclosed equipment.
Type 2 Enclosure: Intended for indoor use primarily to provide a degree of protection against limited amounts of falling water and dirt.
Type 3 Enclosure: Intended for outdoor use primarily to provide a degree of protection against wind-blown dust, rain, sleet and external ice formation.
Type 3R Enclosure: Intended for outdoor use primarily to provide a degree of protection against falling rain, sleet and external ice formation.
Type 3S Enclosure: Intended for outdoor use primarily to provide a degree of protection against windblown dust, rain, and sleet, and to provide for operation of external mechanism when ice laden.
Type 3X Enclosure: Intended for outdoor use primarily to provide a degree of protection against corrosion, wind-blown dust, rain, sleet and external ice formation.
Type 3SX Enclosure: Intended for outdoor use primarily to provide a degree of protection against corrosion, wind-blown dust, rain, and sleet, and to provide for operation of external mechanism when ice laden.
Type 4 Enclosure: Intended for indoor or outdoor use primarily to provide a degree of protection against wind-blown dust and rain, splashing water and hose-directed water.
Type 4X Enclosure: Intended for indoor or outdoor use primarily to provide a degree of protection against corrosion, wind-blown dust and rain, splashing water and hose-directed water.
Type 6 Enclosure: Intended for indoor or outdoor use primarily to avoid a degree of protection against contact with enclosed equipment, falling dirt, hose-directed water, entry of water during occasional temporary submersion at a limited depth and external ice formation.
Type 6P Enclosure: Intended for indoor or outdoor use primarily to provide a degree of protection against contact with enclosed equipment, falling dirt, hose-directed water, entry of water during prolonged submersion at a limited depth and external ice formation.
Type 12 Enclosure: Intended for indoor use primarily to provide a degree of protection against dust, falling dirt and dripping noncorrosive liquids.
Type 13 Enclosure: Intended for indoor use primarily to provide a degree of protection against dust, spraying of water, oil and noncorrosive coolant.
IP (Ingress Protection) Rating for Equipment and Enclosures
A two-digit number (as specified in Australian Standards AS60529 and EN60529) is used to provide an IP Rating to a piece of electronic equipment or to an enclosure for electronic equipment.
The two digits represent three different forms of environmental influence:
The first digit represents protection against ingress of solid objects
The second digit represents protection against ingress of liquids
The larger the value of each digit, the greater the protection from that influence. As an example, a product rated as IP57 would be better protected against environmental factors than another similar product that was only rated as IP43. Our Gel Connectors are rated at IP67 (totally protected against dust ingress and withstands immersion up to a depth of 1 metre).
Value First Digit Second Digit
Protection against ingress Protection against ingress
of solids of liquids
0 No protection No protection
1 Protected against solid Protected against vertically
objects over 50mm e.g. falling drops of water.
hands, large tools
2 Protected against solid objects over Protected against direct sprays of water up to 15°
12mm e.g. hands, large tools from vertical.
3 Protected against solid objects over Protected against direct sprays of water up to 60°
2.5mm e.g. wire, small tools from vertical.
4 Protected against solid objects over Protected against water sprayed from any direction.
1.0mm e.g. wires Limited ingress permitted.
5 Limited protection against dust ingress Protected against low pressure water jets from any
(no harmful deposit) direction. Limited ingress permitted.
6 Totally protected against dust ingress. Protected against high pressure water jets from any
direction. Limited ingress permitted.
7 - Protected against immersion between 15cm and 1M.
8 - Protected against long periods of immersion under pressure.
9 - -
Inconel(From Wikipedia)
Inconel is a registered trademark of Special Metals Corporation that refers to a family of austenitic nickel-chromium-based superalloys.[1] Inconel alloys are typically used in high temperature applications. It is often referred to in English as "Inco" (or occasionally "Iconel"). Common trade names for Inconel include: Inconel 625, Chronin 625, Altemp 625, Haynes 625, Nickelvac 625 and Nicrofer 6020.[2]
Composition
Different Inconels have widely varying compositions, but all are predominantly nickel, with chromium as the second element.
Properties
Inconel alloys are oxidation and corrosion resistant materials well suited for service in extreme environments. When heated, Inconel forms a thick, stable, passivating oxide layer protecting the surface from further attack. Inconel retains strength over a wide temperature range, attractive for high temperature applications where aluminum and steel would succumb to creep as a result of thermally-induced crystal vacancies (see Arrhenius equation). Inconel's high temperature strength is developed by solid solution strengthening or precipitation strengthening, depending on the alloy. In age hardening or precipitation strengthening varieties, small amounts of niobium combine with nickel to form the intermetallic compound Ni3Nb or gamma prime (γ'). Gamma prime forms small cubic crystals that inhibit slip and creep effectively at elevated temperatures.
Machining
Inconel is a difficult metal to shape and machine using traditional techniques due to rapid work hardening. After the first machining pass, work hardening tends to plastically deform either the workpiece or the tool on subsequent passes. For this reason, age-hardened Inconels such as 718 are machined using an aggressive but slow cut with a hard tool, minimizing the number of passes required. Alternatively, the majority of the machining can be performed with the workpiece in a solutionised form, with only the final steps being performed after age-hardening. External threads are machined using a lathe to "single point" the threads, or by rolling the threads using a screw machine. Holes with internal threads are made by welding or brazing threaded inserts made of stainless steel. Cutting of plate is often done with a waterjet cutter. Internal threads can also be cut by single point method on lathe, or by threadmilling on a machining center. New whisker reinforced ceramic cutters are also used to machine nickel alloys. They remove material at a rate typically 8 times faster than carbide cutters. 718 Inconel can also be roll threaded after full aging by using induction heat to 1300 degrees F without increasing grain size.[citation needed]
Joining
Welding inconel alloys is difficult due to cracking and microstructural segregation of alloying elements in the heat affected zone. However, several alloys have been designed to overcome these problems. The most common welding method is gas tungsten arc welding.[7]
New innovations in pulsed micro laser welding have also become more popular in recent years.
Uses
Inconel is often encountered in extreme environments. It is common in gas turbine blades, seals, and combustors, as well as turbocharger rotors and seals, electric submersible well pump motor shafts, high temperature fasteners, chemical processing and pressure vessels, heat exchanger tubing, steam generators in nuclear pressurized water reactors, natural gas processing with contaminants such as H2S and CO2, firearm sound suppressor blast baffles, and Formula One and NASCAR exhaust systems.[8][9] Inconel is increasingly used in the boilers of waste incinerators.[10] The Joint European Torus vessel is made in Inconel.[11] Inside JET a plasma is heated to temperatures that are higher than those found in the Sun. A strong magnetic field keeps the plasma away from the vessel.
North American Aviation constructed the skin of the X-15 rocket plane out of an Inconel alloy known as "Inconel X".[12]
Rolled Inconel was frequently used as the recording medium by engraving in Black Box recorders on aircraft[13]
Alternatives to the use of Inconel in chemical applications like scrubber, columns, reactors, and pipes is Hastelloy, perfluoroalkoxy (PFA) lined carbon steel or fiber reinforced plastic.
Inconel alloys
Inconel 600: Solid solution strengthened
Inconel 625: Acid resistant, good weldability
Inconel 690: Low cobalt content for nuclear applications, and low resistivity[14]
Inconel 718: Gamma double prime strengthened with good weldability
Inconel 751: Increased aluminum content for improved rupture strength in the 1600°F range[15]
Inconel 939: Gamma prime strengthened with good weldability
Composition
Different Inconels have widely varying compositions, but all are predominantly nickel, with chromium as the second element.
Properties
Inconel alloys are oxidation and corrosion resistant materials well suited for service in extreme environments. When heated, Inconel forms a thick, stable, passivating oxide layer protecting the surface from further attack. Inconel retains strength over a wide temperature range, attractive for high temperature applications where aluminum and steel would succumb to creep as a result of thermally-induced crystal vacancies (see Arrhenius equation). Inconel's high temperature strength is developed by solid solution strengthening or precipitation strengthening, depending on the alloy. In age hardening or precipitation strengthening varieties, small amounts of niobium combine with nickel to form the intermetallic compound Ni3Nb or gamma prime (γ'). Gamma prime forms small cubic crystals that inhibit slip and creep effectively at elevated temperatures.
Machining
Inconel is a difficult metal to shape and machine using traditional techniques due to rapid work hardening. After the first machining pass, work hardening tends to plastically deform either the workpiece or the tool on subsequent passes. For this reason, age-hardened Inconels such as 718 are machined using an aggressive but slow cut with a hard tool, minimizing the number of passes required. Alternatively, the majority of the machining can be performed with the workpiece in a solutionised form, with only the final steps being performed after age-hardening. External threads are machined using a lathe to "single point" the threads, or by rolling the threads using a screw machine. Holes with internal threads are made by welding or brazing threaded inserts made of stainless steel. Cutting of plate is often done with a waterjet cutter. Internal threads can also be cut by single point method on lathe, or by threadmilling on a machining center. New whisker reinforced ceramic cutters are also used to machine nickel alloys. They remove material at a rate typically 8 times faster than carbide cutters. 718 Inconel can also be roll threaded after full aging by using induction heat to 1300 degrees F without increasing grain size.[citation needed]
Joining
Welding inconel alloys is difficult due to cracking and microstructural segregation of alloying elements in the heat affected zone. However, several alloys have been designed to overcome these problems. The most common welding method is gas tungsten arc welding.[7]
New innovations in pulsed micro laser welding have also become more popular in recent years.
Uses
Inconel is often encountered in extreme environments. It is common in gas turbine blades, seals, and combustors, as well as turbocharger rotors and seals, electric submersible well pump motor shafts, high temperature fasteners, chemical processing and pressure vessels, heat exchanger tubing, steam generators in nuclear pressurized water reactors, natural gas processing with contaminants such as H2S and CO2, firearm sound suppressor blast baffles, and Formula One and NASCAR exhaust systems.[8][9] Inconel is increasingly used in the boilers of waste incinerators.[10] The Joint European Torus vessel is made in Inconel.[11] Inside JET a plasma is heated to temperatures that are higher than those found in the Sun. A strong magnetic field keeps the plasma away from the vessel.
North American Aviation constructed the skin of the X-15 rocket plane out of an Inconel alloy known as "Inconel X".[12]
Rolled Inconel was frequently used as the recording medium by engraving in Black Box recorders on aircraft[13]
Alternatives to the use of Inconel in chemical applications like scrubber, columns, reactors, and pipes is Hastelloy, perfluoroalkoxy (PFA) lined carbon steel or fiber reinforced plastic.
Inconel alloys
Inconel 600: Solid solution strengthened
Inconel 625: Acid resistant, good weldability
Inconel 690: Low cobalt content for nuclear applications, and low resistivity[14]
Inconel 718: Gamma double prime strengthened with good weldability
Inconel 751: Increased aluminum content for improved rupture strength in the 1600°F range[15]
Inconel 939: Gamma prime strengthened with good weldability
2009年3月9日 星期一
Extraction and separation technology of aniseed shikimic acid(專利)
Extraction and separation technology of aniseed shikimic acid
Patent Number(s): CN100999461-A
Inventor(s): MIN Y, LIU W, YANG J
Patent Assignee(s) and Codes(s):HONGHE INST (HONG-Non-standard)
Derwent Primary Accession Number: 2008-A50137 [04]
Abstract: NOVELTY - The invention claims an extraction and separation technology of aniseed shikimic acid. Its main steps are to degrease the dry crashed aniseed at 40~45 centigrade, 25~35 MPa through supercritical carbon dioxide to get edible flavor; leaching extract by heating and refluxing at 50~60 centigrade through carbinol after degreasing; extracting at 50~55 centigrade through ethyl acetate and then filtering and separating ethyl acetate to get solid extract; adding carbinol at 50~60 centigrade, heating and churning up until extract dissolves and then filtering, placing the filtered liquid still and cooling to get crystal-the coarse shikimic acid; dissolving the coarse shikimic acid at 45~50 centigrade through mixed solvent of chloroform and carbinol, placing naturally, cooling crystal and then purifying to get purified product, whose purity is larger than 95%. The invention adopts supercritical carbon dioxide to degrease, so that the aniseed oil can be used as flavor and can be eaten directly, it has no harm to human body. This technology improves the use of aniseed, improves degreasing efficiency and reduces the effect of liposoluble ingredients to the later operation so that it improves the recovery rate.
Show Documentation Abstract
International Patent Classification: A61K-036/185; A61K-036/57; A61K-131/00; C07C-051/42; C07C-062/00; C07C-062/04
Derwent Class Code(s): B04 ; B05
Derwent Manual Code(s): B04-A08C2; B04-B01C1; B10-C04A; B11-B03
Patent Details:
Patent Number
Publ. Date
Main IPC
Week
Page Count
Language
CN100999461-A
18 Jul 2007
C07C-051/42
200804
Application Details:
CN100999461-A
CN10065617
13 Jan 2007
Priority Application Information and Date:
CN10065617
13 Jan 2007
Patent Number(s): CN100999461-A
Inventor(s): MIN Y, LIU W, YANG J
Patent Assignee(s) and Codes(s):HONGHE INST (HONG-Non-standard)
Derwent Primary Accession Number: 2008-A50137 [04]
Abstract: NOVELTY - The invention claims an extraction and separation technology of aniseed shikimic acid. Its main steps are to degrease the dry crashed aniseed at 40~45 centigrade, 25~35 MPa through supercritical carbon dioxide to get edible flavor; leaching extract by heating and refluxing at 50~60 centigrade through carbinol after degreasing; extracting at 50~55 centigrade through ethyl acetate and then filtering and separating ethyl acetate to get solid extract; adding carbinol at 50~60 centigrade, heating and churning up until extract dissolves and then filtering, placing the filtered liquid still and cooling to get crystal-the coarse shikimic acid; dissolving the coarse shikimic acid at 45~50 centigrade through mixed solvent of chloroform and carbinol, placing naturally, cooling crystal and then purifying to get purified product, whose purity is larger than 95%. The invention adopts supercritical carbon dioxide to degrease, so that the aniseed oil can be used as flavor and can be eaten directly, it has no harm to human body. This technology improves the use of aniseed, improves degreasing efficiency and reduces the effect of liposoluble ingredients to the later operation so that it improves the recovery rate.
Show Documentation Abstract
International Patent Classification: A61K-036/185; A61K-036/57; A61K-131/00; C07C-051/42; C07C-062/00; C07C-062/04
Derwent Class Code(s): B04 ; B05
Derwent Manual Code(s): B04-A08C2; B04-B01C1; B10-C04A; B11-B03
Patent Details:
Patent Number
Publ. Date
Main IPC
Week
Page Count
Language
CN100999461-A
18 Jul 2007
C07C-051/42
200804
Application Details:
CN100999461-A
CN10065617
13 Jan 2007
Priority Application Information and Date:
CN10065617
13 Jan 2007
2009年3月4日 星期三
膠原蛋白
膠原蛋白是人體的一種非常重要的蛋白質，主要存在於結締組織中。它具有很強的伸張能力，是韌帶和肌鍵的主要成份，膠原蛋白還是細胞外基質的主要組成成分。它使皮膚保持彈性，而膠原蛋白的老化，則使皮膚出現皺紋。膠原蛋白亦是眼睛角膜的主要成份，但以結晶形式組成。
構成膠原的肽鏈，其胺基酸序列非常有特色。首先，它富含甘氨酸和脯氨酸殘基，前者的含量達到總胺基酸殘基的1/3後者則接近1/4；其次，序列中含有不由DNA鹼基三聯密碼子編碼的羥賴氨酸和羥脯氨酸，這兩種胺基酸是在蛋白質一級結構序列形成之後由特定的酶作用於序列中的賴氨酸和脯氨酸形成的；最後，它的序列中只含有很少的酪氨酸殘基;並且不含有色氨酸和半胱氨酸殘基。膠原蛋白一級結構的另一個特點是它的胺基酸的排列。這些胺基酸一般以-甘氨酸-脯氨酸-羥脯氨酸-三聯交替出現的順序排列。只有很少的蛋白質有這樣規則的胺基酸排列。
在空間結構上，膠原蛋白顯示出特殊的三股螺旋纏繞的結構，三條相互獨立的膠原蛋白肽鏈依靠甘氨酸之間形成的氫鍵維繫三股螺旋相互纏繞的結構。膠原蛋白肽鏈的三股螺旋結構不同於普通的α螺旋結構，它的螺距更大，但每一圈螺旋所包含的胺基酸殘基數卻很小，僅為3.3個，因此膠原蛋白的三股螺旋顯得細而長，螺旋中間的空間很小，僅能容納一個氫原子，只有甘氨酸能夠勝任這個位置。另外脯氨酸所特有的肽平面夾角也是形成這種特殊螺旋結構的必須因素。這也是膠原蛋白肽鏈中-甘氨酸-脯氨酸-羥脯氨酸-三聯序列交替出現的原因。膠原蛋白這種特殊的三股螺旋結構保證了它的機械強度。這種三股螺旋被稱為原膠原。
若干個原膠原橫向堆積，序列中所含有的羥賴氨酸和羥脯氨酸側鏈在酶作用下氧化生成醛，相互之前發生羥醛縮合反應形成原膠原之間的共價連結，這種結構被稱為膠原微纖維。許多膠原微纖維橫向堆積，以相同的方式通過共價鍵連結，形成膠原纖維。膠原纖維是膠原蛋白行使生理作用的基本形態，在生物體內膠原纖維交織成富有機械強度合彈性的網狀結構成為結締組織最基本的組成成分。
目前膠原蛋白是非常受到歡迎的保健美容品，使用範圍以整型醫學、營養輔助品、保養品為三大主流，也就是以注射、口服、擦拭為應用。
而其中以注射效果最好但價格昂貴，擦拭則因分子量太大而無法吸收，因此目前較為熱門的是水解過的口服膠原蛋白，不但價格適中且效果好，市面上知名的有台鹽、珍寶三旺、芳珂、金牌、白蘭氏，注射的則有雙美等廠商。
事實上口服的膠原蛋白會受到胃酸破壞，無法吸收，所以口服的膠原蛋白其實對於皮膚的幫助不大，想要皮膚能夠產生膠原蛋白的話，就必須要刺激皮膚表面，讓身體自行生成膠原蛋白，才會有效，目前來說，塗抹左旋Ｃ是副作用最小的方式。
但也有說法指出膠原蛋白是品質較差的蛋白質來源，因為它們沒有全部的必需胺基酸-也就是說它們並不是完全蛋白質(complete protein)。業者聲稱口服膠原蛋白食品能達到改善皮膚、指甲或關節的美容保健功效，但是這個說法並沒有得到任何主流研究結果的支持。通常這些部位有問題的人，比較有可能是因為其他因素造成的，而不是因為飲食中缺乏蛋白質的關係。就算是因為缺乏蛋白質的緣故，蛋白質也能夠由其他較佳的食物來源獲得。
http://zh.wikipedia.org/wiki/%E8%86%A0%E5%8E%9F%E8%9B%8B%E7%99%BD
構成膠原的肽鏈，其胺基酸序列非常有特色。首先，它富含甘氨酸和脯氨酸殘基，前者的含量達到總胺基酸殘基的1/3後者則接近1/4；其次，序列中含有不由DNA鹼基三聯密碼子編碼的羥賴氨酸和羥脯氨酸，這兩種胺基酸是在蛋白質一級結構序列形成之後由特定的酶作用於序列中的賴氨酸和脯氨酸形成的；最後，它的序列中只含有很少的酪氨酸殘基;並且不含有色氨酸和半胱氨酸殘基。膠原蛋白一級結構的另一個特點是它的胺基酸的排列。這些胺基酸一般以-甘氨酸-脯氨酸-羥脯氨酸-三聯交替出現的順序排列。只有很少的蛋白質有這樣規則的胺基酸排列。
在空間結構上，膠原蛋白顯示出特殊的三股螺旋纏繞的結構，三條相互獨立的膠原蛋白肽鏈依靠甘氨酸之間形成的氫鍵維繫三股螺旋相互纏繞的結構。膠原蛋白肽鏈的三股螺旋結構不同於普通的α螺旋結構，它的螺距更大，但每一圈螺旋所包含的胺基酸殘基數卻很小，僅為3.3個，因此膠原蛋白的三股螺旋顯得細而長，螺旋中間的空間很小，僅能容納一個氫原子，只有甘氨酸能夠勝任這個位置。另外脯氨酸所特有的肽平面夾角也是形成這種特殊螺旋結構的必須因素。這也是膠原蛋白肽鏈中-甘氨酸-脯氨酸-羥脯氨酸-三聯序列交替出現的原因。膠原蛋白這種特殊的三股螺旋結構保證了它的機械強度。這種三股螺旋被稱為原膠原。
若干個原膠原橫向堆積，序列中所含有的羥賴氨酸和羥脯氨酸側鏈在酶作用下氧化生成醛，相互之前發生羥醛縮合反應形成原膠原之間的共價連結，這種結構被稱為膠原微纖維。許多膠原微纖維橫向堆積，以相同的方式通過共價鍵連結，形成膠原纖維。膠原纖維是膠原蛋白行使生理作用的基本形態，在生物體內膠原纖維交織成富有機械強度合彈性的網狀結構成為結締組織最基本的組成成分。
目前膠原蛋白是非常受到歡迎的保健美容品，使用範圍以整型醫學、營養輔助品、保養品為三大主流，也就是以注射、口服、擦拭為應用。
而其中以注射效果最好但價格昂貴，擦拭則因分子量太大而無法吸收，因此目前較為熱門的是水解過的口服膠原蛋白，不但價格適中且效果好，市面上知名的有台鹽、珍寶三旺、芳珂、金牌、白蘭氏，注射的則有雙美等廠商。
事實上口服的膠原蛋白會受到胃酸破壞，無法吸收，所以口服的膠原蛋白其實對於皮膚的幫助不大，想要皮膚能夠產生膠原蛋白的話，就必須要刺激皮膚表面，讓身體自行生成膠原蛋白，才會有效，目前來說，塗抹左旋Ｃ是副作用最小的方式。
但也有說法指出膠原蛋白是品質較差的蛋白質來源，因為它們沒有全部的必需胺基酸-也就是說它們並不是完全蛋白質(complete protein)。業者聲稱口服膠原蛋白食品能達到改善皮膚、指甲或關節的美容保健功效，但是這個說法並沒有得到任何主流研究結果的支持。通常這些部位有問題的人，比較有可能是因為其他因素造成的，而不是因為飲食中缺乏蛋白質的關係。就算是因為缺乏蛋白質的緣故，蛋白質也能夠由其他較佳的食物來源獲得。
http://zh.wikipedia.org/wiki/%E8%86%A0%E5%8E%9F%E8%9B%8B%E7%99%BD
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