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When the farmers spray pesticides or other drugs， only 2% of them can be sprayed on plants while most of them are often out of the plant， falling on the land or becoming part of the runoff， leading to soil and water pollution. Recently， the United States Massachusetts Institute of Technology （MIT） research team cleverly added to the spray of two kinds of inexpensive polymer additives， which can significantly reduce the rebound in the amount of liquid.
Many plant leaves have natural hydrophobicity， which is why they rebound drops. The method uses two different types of additives， dividing the spray into two parts， each receiving different polymer substances. One for the positive charge， the other one for the negative charge. When the oppositely charged droplets meet at the blade surface， they form a hydrophilic "defect" that can be attached to the surface， increasing the retention of the droplets.
According to laboratory tests， the team believes that this will enable farmers to achieve the same effect with only 1/10 of the pesticide， and the polymer additive itself is natural， biodegradable and will not add to runoff pollution. And as it is also an ordinary low-cost materials， it can be locally produced.
"Adding polymer additives to the spray， however， requires the use of two cans of conventional sprayers， one tank of one substance， and the other tank of oppositely charged substances，" says graduate student Maher Damak. As a result， the new approach also requires minor modifications to existing equipment used by farmers.
1nanometer
The US Department of Energy Lawrence Berkeley National Laboratory's research team said that using carbon nanotubes and molybdenum disulfide （MoS2）， they have successively made the world's smallest transistors， whose gate length is only 1 nanometer， equivalent to 1/50，000 of the diameter of human hair， far below the theoretical minimum of 5 nanometers of silicon-based transistor’s gate length.
MoS2， like silicon， has a crystalline lattice structure， but the conductivity of molybdenum disulfide is more controllable than silicon， and can be processed to a thickness of only 0.65 nm thick， said researcher Ali Jawi's team. Electric constant （also known as the permittivity） of the lower layer， is the ideal transistor material. While using nanotubes of only one nanometer diameter to make the gate， it is an result fully considering the difficulty of the manufacturing process.
The team's tests showed that the molybdenum disulfide transistor， which uses carbon nanotubes as its gate， can effectively control the current flow. Even if the gate is only 1 nanometer， its electrical performance is still good. "Obtaining marine data through the Internet of things， the construction of marine data intelligent computing platform， the establishment of integrated marine data application system， together play an important supporting role to enhance regional port and shipping， logistics， fisheries， shipping， level of tourism and other service as well as improving deciding abilities of ocean management.”
---Academecian of Chinese Academy of Sciences， Director of National Ocean Laboratory
WU Lixin
Recently， Qingdao Marine Science and Technology National Laboratory announced that the Marine National Laboratory will build supercomputers. The performance of this supercomputer per trillion times per second， whichwill be the fastest in the field of marine computing supercomputer. According to reports， the supercomputer is a large national marine laboratory research platform – as an important content of "petascale high-performance scientific computing and system simulation platform"， it will serve the integration of China's marine data resources and open sharing， to solve the "Fragmentation" problem of marine data.
In addition， the Marine National Laboratory will also establish a joint laboratory of marine intelligent computing and large data， through multidisciplinary integration， technology complementarity， to promote the field of scientific research， technological innovation， localization of core technology and transformation of scientific research and other issues.
Here comes batteries that can be swallowed
Recently， the United States Carnegie Mellon University （Carnegie Mellon University） researchers have developed a biodegradable battery. The battery， which is manufactured as a pill， is a controlled-release device for human swallowing and is capable of accurately and safely supplying power to a controlled-release drug dispenser or monitoring device.
Christopher Bettinger， an associate professor of materials science and biomedical engineering at Carnegie Mellon University， has developed a battery that uses the melanin that the body has long been accustomed to， while the melanin present in human skin， hair and eyes is non-toxic. The researchers said that melanin can absorb ultraviolet light to inhibit free radicals in the human body activities， and can bind and unbind metal ions. In the test phase， the melanoma battery can produce 20-hour power supply for swallowed medical devices.
Many plant leaves have natural hydrophobicity， which is why they rebound drops. The method uses two different types of additives， dividing the spray into two parts， each receiving different polymer substances. One for the positive charge， the other one for the negative charge. When the oppositely charged droplets meet at the blade surface， they form a hydrophilic "defect" that can be attached to the surface， increasing the retention of the droplets.
According to laboratory tests， the team believes that this will enable farmers to achieve the same effect with only 1/10 of the pesticide， and the polymer additive itself is natural， biodegradable and will not add to runoff pollution. And as it is also an ordinary low-cost materials， it can be locally produced.
"Adding polymer additives to the spray， however， requires the use of two cans of conventional sprayers， one tank of one substance， and the other tank of oppositely charged substances，" says graduate student Maher Damak. As a result， the new approach also requires minor modifications to existing equipment used by farmers.
1nanometer
The US Department of Energy Lawrence Berkeley National Laboratory's research team said that using carbon nanotubes and molybdenum disulfide （MoS2）， they have successively made the world's smallest transistors， whose gate length is only 1 nanometer， equivalent to 1/50，000 of the diameter of human hair， far below the theoretical minimum of 5 nanometers of silicon-based transistor’s gate length.
MoS2， like silicon， has a crystalline lattice structure， but the conductivity of molybdenum disulfide is more controllable than silicon， and can be processed to a thickness of only 0.65 nm thick， said researcher Ali Jawi's team. Electric constant （also known as the permittivity） of the lower layer， is the ideal transistor material. While using nanotubes of only one nanometer diameter to make the gate， it is an result fully considering the difficulty of the manufacturing process.
The team's tests showed that the molybdenum disulfide transistor， which uses carbon nanotubes as its gate， can effectively control the current flow. Even if the gate is only 1 nanometer， its electrical performance is still good. "Obtaining marine data through the Internet of things， the construction of marine data intelligent computing platform， the establishment of integrated marine data application system， together play an important supporting role to enhance regional port and shipping， logistics， fisheries， shipping， level of tourism and other service as well as improving deciding abilities of ocean management.”
---Academecian of Chinese Academy of Sciences， Director of National Ocean Laboratory
WU Lixin
Recently， Qingdao Marine Science and Technology National Laboratory announced that the Marine National Laboratory will build supercomputers. The performance of this supercomputer per trillion times per second， whichwill be the fastest in the field of marine computing supercomputer. According to reports， the supercomputer is a large national marine laboratory research platform – as an important content of "petascale high-performance scientific computing and system simulation platform"， it will serve the integration of China's marine data resources and open sharing， to solve the "Fragmentation" problem of marine data.
In addition， the Marine National Laboratory will also establish a joint laboratory of marine intelligent computing and large data， through multidisciplinary integration， technology complementarity， to promote the field of scientific research， technological innovation， localization of core technology and transformation of scientific research and other issues.
Here comes batteries that can be swallowed
Recently， the United States Carnegie Mellon University （Carnegie Mellon University） researchers have developed a biodegradable battery. The battery， which is manufactured as a pill， is a controlled-release device for human swallowing and is capable of accurately and safely supplying power to a controlled-release drug dispenser or monitoring device.
Christopher Bettinger， an associate professor of materials science and biomedical engineering at Carnegie Mellon University， has developed a battery that uses the melanin that the body has long been accustomed to， while the melanin present in human skin， hair and eyes is non-toxic. The researchers said that melanin can absorb ultraviolet light to inhibit free radicals in the human body activities， and can bind and unbind metal ions. In the test phase， the melanoma battery can produce 20-hour power supply for swallowed medical devices.