In November 2009, the Ministry of Agriculture approved the issuance of a production and application safety certificate for some genetically modified crops. Since then, the safety issue of genetically modified crops has caused fierce debates in all walks of life in our country.
GM technology can solve the problems faced by human beings such as food shortages, energy crisis, and lack of resources. However, due to the need to assess the performance traits and genetic variation effects of genetically modified varieties, public suspicions are constantly heard. In interviews for genetically modified issues, scientists and communication experts have repeatedly stressed that media reports and some rumors on the website cannot be evidenced in terms of genetic modification or other scientific issues unless they are published in a professional scientific journal.
Perhaps not all issues require scientific evidence, but genetically modified safety can only be a question that needs to be answered by scientific methods and scientific methods.
"After the transgene enters the human body, it will be digested into single nucleotides and no longer contain genetic information."
Science and Technology Daily: GM crops can improve the varieties of genetically modified products and increase nutrient content, reduce the content of allergenic substances and toxic substances, delay the maturity, but also can increase the starch content and extend the product's preservation time. However, some people worry that this change will make crops unsafe and worry about genetic variation. What do you think?
Zhu Xi (researcher and doctoral supervisor of the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences): Compared with traditional breeding techniques, transgenic breeding has the following characteristics: First, the genetic material exchange of traditional breeding techniques can only be between the same species. To carry out, transgenic technology breaks this restriction and can be carried out between different species; secondly, the traditional breeding technology operates on the entire genome, and it is impossible to accurately select a certain gene, and the transgenic technology transfers the With a well-defined gene, the offspring's traits can be accurately predicted. It can be seen that transgenic technology is the development and supplement of traditional technologies, and it is more accurate, safe, and controllable. It will only change the genetic characteristics of crops such as resistance to insects and stress, rather than changing the genetic laws of crops.
Compared with traditional crops cultivated and cultivated by humans for more than a thousand years, the emergence of genetically modified crops has been only more than 20 years. Therefore, some people questioned that after eating genetically modified foods, genetic modification will be absorbed by the human body and cause potential risks. In fact, this is completely a misunderstanding. Any kind of food derived from animals and plants itself contains 30,000 to 50,000 genes. Genetically modified foods are only one or two more than the original food. The nature of the transgene is exactly the same as that of other genes. When all these genes enter the human body, they are digested into individual nucleotides and no longer contain any genetic information. Many animal and vegetable foods that humans have eaten for thousands of years have also contained thousands of genes. No one has ever feared that they will change human genes or be passed on to future generations. This phenomenon has never occurred.
Science and Technology Daily: GM has changed the composition and proportion of chemical components in grain and oil foods to improve their food quality or processing characteristics, meet the dietary needs of different groups, increase their added value, etc. Whether this change is also safe and how long it takes To test?
Zhu Xi: The target substance expressed in GM crops is protein, which has no essential difference from the protein in food. If the protein is a sensitizer or toxin, it will be acute in the human body, otherwise it will be digested, absorbed and utilized by the body, so it will not accumulate in the human body, it will not cause problems because of long-term consumption. This is not the same as heavy metal pollution. Heavy metals cannot be metabolized and will gradually accumulate. Therefore, it may be no problem to eat short-term food, but there will be problems in long-term consumption.
“Genetical seeds do not rely heavily on herbicides, herbicide-resistant varieties are beneficial for crop rotation and no-tillage, cost savingsâ€
Science and Technology Daily: Will the genetically modified seeds depend heavily on herbicides? What are the current developments and studies on this issue? Because of the widespread use of herbicides, weed herbicide-resistant super weeds will appear. If so, how should we respond?
Wan Jianmin (Director of Crop Science Research Institute, Chinese Academy of Agricultural Sciences): GM seeds do not rely heavily on herbicides. This feature is adapted to the need to kill weeds. The cultivation and application of herbicide-resistant varieties are beneficial to crop rotation and no-tillage, save costs, increase farmers' income, and reduce soil erosion, which is a breakthrough in soybean production. By revolving it is possible to avoid dependence on herbicides. At present, there are two main types of herbicide-tolerant soybeans that are commercially grown: the first is Roundup Ready, a glyphosate-resistant soybean variety from Monsanto, and the second is Bayer CropScience's Liberty Link, a glufosinate-resistant soybean variety. China has cultivated a new line of herbicide-resistant soybeans with industrialization prospects.
The emergence of drug-resistant weeds is based on the genetic differences among weed populations and the selective pressure of herbicides. Genetic differences within a weed population can either be present intrinsically or can be due to mutations. The intensity of the selection pressure is determined by the amount of herbicide used, the frequency of use, and the period of validity. Continuous use of certain herbicides will increase the pressure of selection and will make the weeds resistant to insecticides. The solutions include: First, cultivating and promoting transgenic soybeans resistant to different types of herbicides, such as glyphosate-tolerant, Dicamba, 2,4-D, HPPD-inhibiting herbicides, etc.; and secondly, rational rotation of herbicides with different mechanisms of action. Resistant weeds can be avoided and eliminated.
“The real benefit of planting genetically modified soybeans is farmers.â€
Science and Technology Daily: After planting genetically modified soybeans in Argentina, only herbicides produced by Monsanto can be used, because this herbicide can remove all weeds, only Monsanto's soybean seeds are tolerant to them, herbicides are sprayed by machines, making Argentina’s national crops are also killed as weeds, the extinction of native seeds and the impact of traditional farming areas. Will this situation worsen the poverty of farmers in Argentina?
Wan Jianmin: The so-called "Argentina's lessons for planting genetically modified soybeans" originated in the book "Food Crisis" introduced by American geopolitical scholar Ndall. Regarding the argument that genetically modified crops have destroyed Argentina's agriculture, they believe that Argentine grows genetically modified soybeans. Large-scale forests make way for soybean fields, traditional crops make way for soybeans, machines replace labor, and farmers are impoverished. However, the actual situation is far from the case. In 2009, the statistics from the National Bureau of Statistics of Argentina showed that in the first quarter, Argentina’s exports amounted to US$15.789 billion, of which agricultural products such as cereals and oil crops grew fastest. The real benefit of planting genetically modified soybeans is farmers. The data from the agricultural survey report in Argentina shows that in more than ten years of planting and harvesting, farmers’ income has increased significantly.
Science and Technology Daily: What technologies do GM crops increase production? What is the impact of climate on genetically modified crops?
Wan Jianmin: On the one hand, transgenic crops can directly increase the yield of crops by transferring foreign genes. For example, IPA1, an ideal plant type major gene cloned in rice, can make rice plants produce thick stalks and increase the number of grains per spike. The output increased by about 10%. On the other hand, it can also indirectly increase crop yield by controlling pests or weeds. For example, the widely planted transgenic Bt cotton has effectively controlled the damage of cotton bollworm. After planting Bt transgenic cotton, the number of bollworms has decreased significantly, and the cotton yield has increased by 15% to 20%. In the United States, Brazil, and Argentina, the use of herbicide-tolerant genetically modified soybeans has changed the traditional farming model and achieved close planting. Soybean production increased by about 9%.
Crop production is affected by a variety of climatic factors. According to the latest research from the International Rice Research Institute, as long as the average temperature rises, it will reduce grain production by 10%. At present, the impact of global climate change has attracted widespread attention and relevant research is being actively carried out. Among them, the use of genetically modified technology to cultivate new stress-tolerant varieties that respond to adverse climate changes is one of the important measures.
Swing bearing
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2.we have the most professional technologist,they have been worked for worldwide famous slewing bearing
company for years .
3.we supply slewing bearing for many Chinese excavator /loader factories .
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5.Professional installation is highly recommended.
About our Slewing Rings
| Name | slewing ring bearing / Excavator SWING CIRCLE |
| Suitable Brand | Excavator |
| Suitable Model | Excavator |
| Original | China |
| AplliCartion | Excavator |
| Warranty |
One year |
| Delivery time | wihtin 3 days after payment confirmed |
| MOQ | 1 set |
| Packing | standard export carton & wooden case or as your require |
Many types of excavator slewing bearing for your purchase.
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Excavator Brand |
Model No. |
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| Excavator |
PC30 |
PC40 |
PC60-6 (Z=76) |
PC60-6 (Z=80) |
PC60-7 (Z=76) |
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PC70-7 |
PC75U |
PC90 |
PC90-6 |
PC100-5 |
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PC120-5 |
PC120-6 (4D95) |
PC120-6 (4D102) |
PC130-7 |
PC128UU |
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|
PC150-5 |
PC20HT |
PC200-1 |
PC200-2 |
PC200-3 |
|
|
PC220-3 |
PC220-5 |
PC200-6 (S6D95) |
PC200-6P (S6D102) |
PC200-7 (Z=92) |
|
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PC220-7 |
PC228UU |
PC300-2 |
PC300-3 |
PC300-5 |
|
|
PC300-6 |
PC300-7 |
PC350-6 |
PC360-7 |
PC400-3 |
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PC400-5 |
PC400-6 |
PC450 |
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| Excavator |
HD450-7 |
HD512 |
HD100 |
HD700-1 |
HD700-2 |
|
HD700-5 |
HD700-7 |
HD770SE |
HD770-1 |
HD770-2 |
|
|
HD800-7 |
HD820-1 |
HD900-7 |
HD1250-5 |
HD250-5 |
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|
HD250-7 |
HD307 |
HD516 |
HD400-7 |
HD450-5 |
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| Excavator | |||||
| Excavator |
EX60-1 |
EX60-2 |
EX60-3 |
EX60-5 |
EX90 |
|
EX100-1 |
EX100-3 |
EX100-5 |
EX120-1 |
EX120-2 |
|
|
EX200-3 |
EX200-5 |
EX210-5 |
ZX120 |
ZX160 |
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|
EX200-1 |
EX200-2 |
EX200-3 |
EX200-5 |
EX210-5 |
|
|
ZX200 |
ZX200-3 |
ZX225 |
EX220-5 |
ZX230 |
|
|
ZX240 |
ZX270 |
EX300-1 |
EX300-2 |
EX300-3 |
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EX300-5 |
ZX330 |
EX450 |
ZX480 |
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| Excavator |
DH55-5 |
DH60-7 |
DH150-7 |
DH200-3 |
DH220-3 |
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DH102 |
DH225-7 |
DH258-7 |
DH280 |
DH290 |
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DH300-5 |
DH320 |
DH330-3 |
DH360-5 |
DH500 |
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| Excavator |
SK03 |
SK09 |
SK907B |
SK100 |
SK120-5 |
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SK200-1 |
SK200-2 |
SK200-5 |
SK200-6 |
SK200-8 |
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|
SK230-6 |
SK300 |
SK350-8 |
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| Excavator |
SH120A2 |
SH120A3 |
SH200A1 |
SH200A2 |
SH200A3 |
|
SH200G3 |
SH200C3 |
SH210A3 |
SH220A1 |
SH225 |
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|
SH260 |
SH265 |
SH280 |
SH300/A2 |
SH340 |
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SH350 |
SH430 |
SH40T |
SH580 |
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| Excavator |
R60-5 |
R60-7 |
R80-7 |
R130-5 |
R130-7 |
|
R140 |
R150W |
R170 |
R200 |
R210-3 |
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|
R220-5 |
R210-9 |
R215-7 |
R225-7 |
R245 |
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|
R260-5 |
R280 |
R290 |
R300 |
R305-7 |
|
|
R320 |
R335-7 |
R360 |
R450 |
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| Excavator |
EC55 |
EC210 |
EC240 |
EC290 | EC360 |
Excavator swing bearing is divided into various specifiCartions:
1.single-row ball slewing bearings with outer teeth or inner teeth , or without teeth;
2.single-row cross roller slewing bearings;
3.double-row different diameter balls slewing bearings;
4.three-row roller slewing bearings and etc.
AppliCartion:
1.Construction Machinery : Cranes, Excavators
2.Mining/Heavy Equipments
3.Port/Marine/Offshore Machinery
4.Forest Industries Equipment
The single-row four points contact ball Slewing Bearing is composed of 2 seat-rings.It features compact in design,and light in weight.
The balls contact with the circular race at four points,via which the axial force,radial force and resultant moment may be born simultaneously.
It may be used for slewing conveyers,welding arms and positioners,light,medium duty cranes,excavators and other engineering machines.
Slewing Ring Bearing Features:
1.High load-carrying capability
2.Ability to accept the combined loads;axial ,radial and tilting moments
3.Flexibility with product design.
4.42CrMo/50Mn material be used to make slewing ring bearing
Product Catalog
1. Single row four point contact ball series.
2. Single-row crossed roller series.
3. Double row ball series.
4. Three-row roller series.
5. Roller and ball combination series.
6. Lightweight outline slewing ring.
Slew bearing for Single-row ball(HS Series)
1. Id:320-4500 Od:550-4500mm
2.material: 52Mn,42CrMo
3.OME service
4.ISO9001-2000 certifiCarte
5.R&D capacity
6.Tolerance:ABEC-1 standard
7.Basic loading rating:Dynamic & Static depend on different model
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Dimensions |
Mount dimensions |
Number of holes |
Gear parameters |
Designation |
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mm |
mm |
m |
mm |
z |
mm |
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|
D |
d |
T |
H |
h |
D1 |
d1 |
dn |
n |
n1 |
Da |
b |
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|
662 |
458 |
80 |
70 |
10 |
626 |
494 |
18 |
20 |
4 |
5 |
689 |
135 |
60 |
011.30.560 |
|
662 |
458 |
80 |
70 |
10 |
626 |
494 |
18 |
20 |
4 |
6 |
688.8 |
112 |
60 |
012.30.560 |
|
732 |
528 |
80 |
70 |
10 |
696 |
564 |
18 |
24 |
4 |
6 |
772.8 |
126 |
60 |
011.30.630 |
|
732 |
528 |
80 |
70 |
10 |
696 |
564 |
18 |
24 |
4 |
8 |
774.4 |
94 |
60 |
012.30.630 |
|
812 |
608 |
80 |
70 |
10 |
776 |
644 |
18 |
24 |
4 |
6 |
850.8 |
139 |
60 |
011.30.710 |
|
812 |
608 |
80 |
70 |
10 |
776 |
644 |
18 |
24 |
4 |
8 |
854.4 |
104 |
60 |
012.30.710 |
|
922 |
678 |
100 |
20 |
10 |
878 |
722 |
22 |
30 |
6 |
8 |
966.4 |
118 |
80 |
011.40.800 |
|
922 |
678 |
100 |
20 |
10 |
878 |
722 |
22 |
30 |
6 |
10 |
968 |
94 |
80 |
012.40.800 |
|
1022 |
778 |
100 |
90 |
10 |
978 |
822 |
22 |
30 |
6 |
8 |
1062.4 |
130 |
80 |
011.40.900 |
|
1022 |
778 |
100 |
90 |
10 |
978 |
822 |
22 |
30 |
6 |
10 |
1068 |
104 |
80 |
012.40.900 |
|
1122 |
878 |
100 |
90 |
10 |
1078 |
922 |
22 |
36 |
6 |
10 |
1188 |
116 |
80 |
011.40.1000 |
|
1122 |
878 |
100 |
90 |
10 |
1078 |
922 |
22 |
36 |
6 |
12 |
1185.6 |
96 |
80 |
012.40.1000 |
Crane Slewing Bearing,Turntable Slewing Ring Bearing,Excavator Turntable Slewing Ring Bearing,,Four Point Slewing Ring Bearing
Shijiazhuang Longshu Mechanical & Electrical Equipment Trading Co., Ltd. , https://www.longsbearings.com