วันพฤหัสบดีที่ 5 กันยายน พ.ศ. 2556

Mount. Fuji!!!!

          

Mount Fuji (富士山, Fujisan) is with 3776 meters Japan's highest mountain. It is not surprising that the nearly perfectly shaped volcano has been worshiped as a sacred mountain and experienced big popularity amongartists and common people throughout the centuries.

Mount Fuji is an active volcano, which most recently erupted in 1708. It stands on the border betweenYamanashi and Shizuoka Prefectures and can be seen from Tokyo and Yokohama on clear days.

Another easy way to view Mount Fuji is from the train on a trip between Tokyo and Osaka. If you take theshinkansen from Tokyo in direction of NagoyaKyoto and Osaka, the best view of the mountain can be enjoyed from around Shin-Fuji Station on the right hand side of the train, about 40-45 minutes into the journey.

Note however, that clouds and poor visibility often block the view of Mount Fuji, and you have to consider yourself lucky if you get a clear view of the mountain. Visibility tends to be better during the colder seasons of the year than in summer, and in the early morning and late evening hours than during the middle of the day.

If you want to enjoy Mount Fuji at a more leisurely pace and from a nice natural surrounding, you should head to the Fuji Five Lake (Fujigoko) region at the northern foot of the mountain, or to Hakone, a nearby hot springresort. Mount Fuji is officially open for climbing during July and August via several routes.


Zurich,Switzerland

Zurich City Guide

Zurich City Guidephoto by Juan Rubiano (www.juanrubiano.com)
Summer is of course the festival season, and several of the early open-airs in Switzerland bore the brunt of the cold and rain (we'll spare you the muddy details...). But in Zurich most of the festivals are in August and September – while summer slowly turns to autumn some of the city's most atmospheric cultural events take place. For rock and electro, there is the Zurich Openair, for theatre and dance productions from around the world the Theater Spektakel on the lake is the place to be, and at the end of September Zurich's now well established film festival gets going. Lots to look forward to!
 
There's plenty of alternatives to festivals too. If you're into sports, go support one of the city's football teams in a Swiss league match. Or delight in an opera performance when the season opens at the end of September. And while the weather holds there are so many lovely outdoor spots in town – open air-bars and restaurantsswimming and much more. We just hope the sun will still be shining when you're reading this.

Gregor Mendel

Gregor Mendel 

Gregor Johan Mendel was born on 20th July 1822, in the Austrian Silesia (now Hynčice, Czech Republic), his parents, Rosine and Anton were farmers and the Mendel family had lived and worked on the farm for over 130 years. Mendel was a keen gardener and Beekeeper during his childhood at the farm.

Mendel studied Physics at the University of Olomouc, and in 1843 he joined the Augustinian Abbey in Old Brno as a novice under Abbot C. F. Napp. Napp was considered to be a huge influence in his life and encouraged Mendel to continue his education. In 1851 Mendel attended the University of Vienna, where he studied physics (under Christian Doppler), Mathematics and Natural History. In 1853, Mendel returned to the Abbey to teach – primarily physics, but he also continued his gardening and from 1854-64, he carried out his famous experimental work in plant hybridization of garden peas, Pisum sativum.

In 1862, Mendel read Charles Darwin’s book The Origin of Species – at the Mendel Museum you can view the book (a German translation of the second edition) and see where Mendel made notes in the margins.

Between 1856 and 1863 Mendel cultivated and tested around 29,000 pea plants, and his study showed that one in four pea plants had purebred recessive alleles, two out of four were hybrid and one out of four were purebred dominant. His experiments led him to make two generalizations, the Law of Segregation and the Law of Independent Assortment, which later became known as Mendel’s Laws of Inheritance.

In 1865, Mendel gave lectures on his experiments at the February and March meetings for the Natural Science Society (Brno), a society Mendel himself had co-founded in 1961. In 1966 Mendel published his findings in the journalProceedings of the Natural History Society of Brünn. Unfortunately the main focus of the paper was on hybridization, not inheritance and it made little impact – being cited only a few times over the next 3 decades.

After completing his work in peas, Mendel extended his experiments to his much loved honey bees, however in 1968 Mendel was made Abbot and his experiments had to take a back seat as his time was take up with administrable duties. Mendel died on the 6th January 1884, in Brno from Chronic Nephritus. His work on inheritance was not rediscovered until the early twentieth Century, and his paper on hybridization is now considered his seminal work. Mendelian Genetics is taught to school children around the world and he is now considered to be the ‘Father’ of modern genetics.NAME: Gregor Mendel
BORN: 20th July 1822
DIED: 6th January 1884
NATIONALITY: Czech

 

 

Gregor Johan Mendel was born on 20th July 1822, in the Austrian Silesia (now Hynčice, Czech Republic), his parents, Rosine and Anton were farmers and the Mendel family had lived and worked on the farm for over 130 years. Mendel was a keen gardener and Beekeeper during his childhood at the farm.

Mendel studied Physics at the University of Olomouc, and in 1843 he joined the Augustinian Abbey in Old Brno as a novice under Abbot C. F. Napp. Napp was considered to be a huge influence in his life and encouraged Mendel to continue his education. In 1851 Mendel attended the University of Vienna, where he studied physics (under Christian Doppler), Mathematics and Natural History. In 1853, Mendel returned to the Abbey to teach – primarily physics, but he also continued his gardening and from 1854-64, he carried out his famous experimental work in plant hybridization of garden peas, Pisum sativum.

In 1862, Mendel read Charles Darwin’s book The Origin of Species – at the Mendel Museum you can view the book (a German translation of the second edition) and see where Mendel made notes in the margins.

Between 1856 and 1863 Mendel cultivated and tested around 29,000 pea plants, and his study showed that one in four pea plants had purebred recessive alleles, two out of four were hybrid and one out of four were purebred dominant. His experiments led him to make two generalizations, the Law of Segregation and the Law of Independent Assortment, which later became known as Mendel’s Laws of Inheritance.

In 1865, Mendel gave lectures on his experiments at the February and March meetings for the Natural Science Society (Brno), a society Mendel himself had co-founded in 1861. In 1866 Mendel published his findings in the journalProceedings of the Natural History Society of Brünn. Unfortunately the main focus of the paper was on hybridization, not inheritance and it made little impact – being cited only a few times over the next 3 decades.

After completing his work in peas, Mendel extended his experiments to his much loved honey bees, however in 1868 Mendel was made Abbot and his experiments had to take a back seat as his time was take up with administrable duties. Mendel died on the 6th January 1884, in Brno from Chronic Nephritus. His work on inheritance was not rediscovered until the early twentieth Century, and his paper on hybridization is now considered his seminal work. Mendelian Genetics is taught to school children around the world and he is now considered to be the ‘Father’ of modern genetics.Gregor Johan Mendel was born on 20thJuly 1822, in the Austrian Silesia (now Hynčice, Czech Republic), his parents, Rosine and Anton were farmers and the Mendel family had lived and worked on the farm for over 130 years. Mendel was a keen gardener and Beekeeper during his childhood at the farm.

Mendel studied Physics at the University of Olomouc, and in 1843 he joined the Augustinian Abbey in Old Brno as a novice under Abbot C. F. Napp. Napp was considered to be a huge influence in his life and encouraged Mendel to continue his education. In 1851 Mendel attended the University of Vienna, where he studied physics (under Christian Doppler), Mathematics and Natural History. In 1853, Mendel returned to the Abbey to teach – primarily physics, but he also continued his gardening and from 1854-64, he carried out his famous experimental work in plant hybridization of garden peas, Pisum sativum.

In 1862, Mendel read Charles Darwin’s book The Origin of Species – at the Mendel Museum you can view the book (a German translation of the second edition) and see where Mendel made notes in the margins.

Between 1856 and 1863 Mendel cultivated and tested around 29,000 pea plants, and his study showed that one in four pea plants had purebred recessive alleles, two out of four were hybrid and one out of four were purebred dominant. His experiments led him to make two generalizations, the Law of Segregation and the Law of Independent Assortment, which later became known as Mendel’s Laws of Inheritance.

In 1865, Mendel gave lectures on his experiments at the February and March meetings for the Natural Science Society (Brno), a society Mendel himself had co-founded in 1961. In 1966 Mendel published his findings in the journalProceedings of the Natural History Society of Brünn. Unfortunately the main focus of the paper was on hybridization, not inheritance and it made little impact – being cited only a few times over the next 3 decades.

After completing his work in peas, Mendel extended his experiments to his much loved honey bees, however in 1968 Mendel was made Abbot and his experiments had to take a back seat as his time was take up with administrable duties. Mendel died on the 6th January 1884, in Brno from Chronic Nephritus. His work on inheritance was not rediscovered until the early twentieth Century, and his paper on hybridization is now considered his seminal work. Mendelian Genetics is taught to school children around the world and he is now considered to be the ‘Father’ of modern genetics.Gregor Johan Mendel was born on 20thJuly 1822, in the Austrian Silesia (now Hynčice, Czech Republic), his parents, Rosine and Anton were farmers and the Mendel family had lived and worked on the farm for over 130 years. Mendel was a keen gardener and Beekeeper during his childhood at the farm.

Mendel studied Physics at the University of Olomouc, and in 1843 he joined the Augustinian Abbey in Old Brno as a novice under Abbot C. F. Napp. Napp was considered to be a huge influence in his life and encouraged Mendel to continue his education. In 1851 Mendel attended the University of Vienna, where he studied physics (under Christian Doppler), Mathematics and Natural History. In 1853, Mendel returned to the Abbey to teach – primarily physics, but he also continued his gardening and from 1854-64, he carried out his famous experimental work in plant hybridization of garden peas, Pisum sativum.

In 1862, Mendel read Charles Darwin’s book The Origin of Species – at the Mendel Museum you can view the book (a German translation of the second edition) and see where Mendel made notes in the margins.

Between 1856 and 1863 Mendel cultivated and tested around 29,000 pea plants, and his study showed that one in four pea plants had purebred recessive alleles, two out of four were hybrid and one out of four were purebred dominant. His experiments led him to make two generalizations, the Law of Segregation and the Law of Independent Assortment, which later became known as Mendel’s Laws of Inheritance.

In 1865, Mendel gave lectures on his experiments at the February and March meetings for the Natural Science Society (Brno), a society Mendel himself had co-founded in 1961. In 1966 Mendel published his findings in the journalProceedings of the Natural History Society of Brünn. Unfortunately the main focus of the paper was on hybridization, not inheritance and it made little impact – being cited only a few times over the next 3 decades.

After completing his work in peas, Mendel extended his experiments to his much loved honey bees, however in 1968 Mendel was made Abbot and his experiments had to take a back seat as his time was take up with administrable duties. Mendel died on the 6th January 1884, in Brno from Chronic Nephritus. His work on inheritance was not rediscovered until the early twentieth Century, and his paper on hybridization is now considered his seminal work. Mendelian Genetics is taught to school children around the world and he is now considered to be the ‘Father’ of modern genetics.

Soil Horizon

Soil Horizon - A soil horizon is a layer of soil or soil material that lies approximately parallel to the land surface.  It differs from adjacent genetically related layers in properties such as color, structure, texture, consistence, and chemical, biological, and mineralogical composition. The presence or absence of certain diagnostic soil horizons determines the place of a soil in the classification system. 


Illustration of soil horizons within a soil profile

Source: Leslie Dampier

If clause

There are three types of the if-clauses.

typecondition
Icondition possible to fulfill
IIcondition in theory possible to fulfill
IIIcondition not possible to fulfill (too late)

Form

typeif clausemain clause
Iwill-future (or Modal + infinitive)
IISimple Past would + infinitive *
IIIPast Perfectwould + have + past participle *

Examples (if-clause at the beginning)

typeif clausemain clause
IIf I study,I will pass the exam.
IIIf I studied,would pass the exam.
IIIIf I had studied,would have passed the exam.

Examples (if-clause at the end)

typemain clauseif-clause
II will pass the examif I study.
IIwould pass the examif I studied.
IIIwould have passed the examif I had studied.

Examples (affirmative and negative sentences)

type Examples
  long formsshort/contracted forms
I+If I study, I will pass the exam.If I study, I'll pass the exam.
-If I study, I will not fail the exam.
If I do not study, I will fail the exam.
If I study, I won't fail the exam.
If I don't study, I'll fail the exam.
II+If I studied, I would pass the exam.If I studied, I'd pass the exam.
-If I studied, I would not fail the exam.
If I did not study, I would fail the exam.
If I studied, I wouldn't fail the exam.
If I didn't study, I'd fail the exam.
III+If I had studied, I would have passedthe exam.If I'd studied, I'd have passed the exam.
-If I had studied, I would not have failedthe exam.
If I had not studied, I would have failedthe exam.
If I'd studied, I wouldn't have failed the exam.
If I hadn't studied, I'd have failed the exam.

* We can substitute could or might for would (shouldmay or must are sometimes possible, too).

would pass the exam.
could pass the exam.
might pass the exam.
may pass the exam.
should pass the exam.
must pass the exam.

Trigonometry

triangleTrigonometry ... is all about triangles.

Right Angled Triangle

right-angled triangle (the right angle is shown by the little box in the corner) has names for each side:

  • Adjacent is adjacent to the angle "θ",
  • Opposite is opposite the angle, and
  • the longest side is the Hypotenuse.
triangle showing Opposite, Adjacent and Hypotenuse

Angles

Angles (such as the angle "θ" above) can be in Degrees or Radians. Here are some examples:

AngleDegreesRadians
right angleRight Angle 90°π/2
__ Straight Angle180°π
right angle Full Rotation360°2π

"Sine, Cosine and Tangent"

The three most common functions in trigonometry are Sine, Cosine and Tangent. You will use them a lot!

They are simply one side of a triangle divided by another.

For any angle "θ":

Right-Angled Triangle
Sine Function:
sin(θ) = Opposite / Hypotenuse
Cosine Function:
cos(θ) = Adjacent / Hypotenuse
Tangent Function:
tan(θ) = Opposite / Adjacent

 

Example: What is the sine of 35°?

Using this triangle (lengths are only to one decimal place):

sin(35°) = Opposite / Hypotenuse = 2.8/4.9 = 0.57...

SineCosine and Tangent are often abbreivated to sincos and tan.

 

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Try It!

Have a try! Drag the corner around to see how different angles affect sine, cosine and tangent

And you will also see why trigonometry is also about circles!

Notice that the sides can be positive or negative according to the rules ofcartesian coordinates. This makes the sine, cosine and tangent vary between positive and negative also.

Unit Circle

What we have just been playing with is the Unit Circle.

It is just a circle with a radius of 1 with its center at 0.

Because the radius is 1, it is easy to measure sine, cosine and tangent.

unit circle

Here you can see the sine function being made by the unit circle:

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You can see the nice graphs made by sine, cosine and tangent.

Repeating Pattern

Because the angle is rotating around and around the circle the Sine, Cosine and Tangent functions repeat once every full rotation.

When you need to calculate the function for an angle larger than a full rotation of 2π (360°) just subtract as many full rotations as you need to bring it back below 2π (360°):

Example: what is the cosine of 370°?

370° is greater than 360° so let us subtract 360°

370° - 360° = 10°

cos(370°) = cos(10°) = 0.985 (to 3 decimal places)

Likewise if the angle is less than zero, just add full rotations.

Example: what is the sine of -3 radians?

-3 is less than 0 so let us add 2π radians

-3 + 2π = -3 + 6.283 = 3.283 radians

sin(-3) = sin(3.283) = -0.141 (to 3 decimal places)

Solving Triangles

A big part of Trigonometry is Solving Triangles. By "solving" I mean finding missing sides and angles.

Example: Find the Missing Angle "C"

 

It's easy to find angle C by using angles of a triangle add to 180°:

So C = 180° - 76° - 34° = 70°

 

It is also possible to find missing side lengths and more. The general rule is:

If you know any 3 of the sides or angles you can find the other 3
(except for the three angles case)

See Solving Triangles for more details.

Other Functions (Cotangent, Secant, Cosecant)

Similar to Sine, Cosine and Tangent, there are three other trigonometric functions which are made by dividing one side by another:

Right-Angled Triangle
Cosecant Function:
csc(θ) = Hypotenuse / Opposite
Secant Function:
sec(θ) = Hypotenuse / Adjacent
Cotangent Function:
cot(θ) = Adjacent / Opposite

 

Trigonometric and Triangle Identities

right angled triangle

The Trigonometric Identities are equations that are true for allright-angled triangles.

triangle

The Triangle Identities are equations that are true for all triangles (they don't have to have a right angle).

 


Valence Electrons

Valence Electrons
Home Up Nuclear Charge Main Energy Levels Valence Electrons Shielding Electrons Efffective Nuclear Charge

 

Valence Electrons

The valence electrons are the electrons in the last shell or energy level of an atom. They do show a repeating or periodic pattern. The valence electrons increase in number as you go across a period. Then when you start the new period, the number drops back down to one and starts increasing again.

For example, when you go across the table from carbon to nitrogen to oxygen, the number of valence electrons increases from 4 to 5 to 6. As we go from fluorine to neon to sodium, the number of valence electrons increases from 7 to 8 and then drops down to 1 when we start the new period with sodium. Within a group--starting with carbon and going down to silicon and germanium--the number of valence electrons stays the same.
   C
4
N
5
O
6
F
7
Ne
8
Na
1
  Si
4
    
   Ge
4
    

A quick way to determine the number of valence electrons for a representative element is to look at which group is it in.  Elements in group Ia have 1 valence electron.  Elements in group IIa have 2 valence electrons.  Can you guess how many valence electrons elements in group VIa have?  If you guessed 6 valence electrons, then you are correct!  The only group of representative elements that this method doesn't work for is group 0.  Those elements certainly have more than 0 valence electrons; in fact, all of them except for helium have 8 valence electrons.  Why doesn't helium have 8 valence electrons?  Think for a moment about how many electrons helium has - it has a total of only two electrons, so helium only has 2 valence electrons. 

So generally speaking, the number of valence electrons stays the same as you go up or down a group, but they increase as you go from left to right across the periodic table. The preceding statement works very well for the representative elements, but it comes a bit short of the truth when you start talking about the transition elements.

 

Electrons going into the d sublevels of the transition metals complicate this pattern. In some ways these electrons behave like valence electrons. In some other ways they behave like shielding electrons, which are discussed in the next section. The first electrons into a d sublevel seem to behave more like valence electrons but the last ones seem to act more like shielding electrons, with variations along the way. Switching the order from 4s3d to 3d4s is one way to represent this.

 ScTiVCrMnFeCoNiCuZn
outer configuration4s23d14s23d24s23d34s13d54s23d54s2
3d6
4s2
3d7
4s2
3d8
3d104s13d104s2
apparent valence electrons32-42-52-62-72 or 32 or 32 or 31 or 22

As it turns out, the idea of valence electrons is not very useful for transition metals, at least not in a reliable, predictable way.

Electron Dot Diagrams

For a chemist, the valence electrons are quite possibly the most important electrons an atom has.  "Why the valence electrons?", you might ask.  Well, since the valence electrons are the electrons in the highest energy level, they are the most exposed of all the electrons ... and, consequently, they are the electrons that get most involved in chemical reactions.   Chemists use a notation called electron dot diagrams, also known as Lewis diagrams, to show how many valence electrons a particular element has.  An electron dot diagram consists of the element's symbol surrounded by dots that represent the valence electrons.  Typically the dots are drawn as if there is a square surrounding the element symbol with up to two dots per side.  (An element will never have more than eight valence electrons.)

As we discussed above, you can determine how many valence electrons an element has by determining which group it is in.  What would the dot diagram for helium look like?  It has 2 valence electrons, so it should have 2 dots like this:    .He.    or    He:

Example 6 in your workbook has a few more dot diagrams to study, then try your hand at the ones in Example 7.

Answers for Example 7:

K is in group Ia, so it has 1 valence electron (1 dot).  

Al is in group IIIa, so it has 3 valence electrons (dots). 

As is in group Va, so it has 5 valence electrons (dots).

F is in group VIIa, so it has 7 valence electrons (dots).